U.S. Route 340 in Maryland
Encyclopedia
U.S. Route 340 is a part of the U.S. Highway System that runs from Greenville, Virginia
to Frederick, Maryland
. In Maryland
, the U.S. highway runs 17.01 miles (27.4 km) from the Virginia
state line at the Potomac River
at Sandy Hook
east to its northern terminus at US 15
and US 40
in Frederick. US 340, which is known for most of its length as Jefferson National Pike, connects Frederick with the communities of Jefferson
, Brunswick
, and Knoxville
in the southern part of the Middletown Valley
of western Frederick County
and Weverton
in far southern Washington County
. The U.S. highway also links Frederick with Harpers Ferry
and Charles Town
in the Eastern Panhandle of West Virginia
. US 340 is a part of the National Highway System
for its entire length in Maryland.
US 340 was one of the original state roads designated by the Maryland State Roads Commission
. The state road was constructed from Frederick to Knoxville in the early 1910s and completed to Harpers Ferry in 1919. The highway was designated Maryland's portion of US 340 in 1926. US 340 originally crossed the Potomac River at Harpers Ferry; however, the U.S. highway's bridge was destroyed by a flood in 1936. The modern US 340 Bridge was constructed at Sandy Hook between 1940 and 1947, with a long interruption due to World War II. The U.S. highway's freeway between Weverton and Frederick was constructed in the 1960s. Old sections of US 340 became part of Maryland Route 180
(MD 180).
just south of the confluence of the Potomac River and the Shenandoah River
at Harpers Ferry. The Potomac Water Gap is where the Potomac River passes between two sets of ridges. The first set of ridges is Elk Ridge
to the north, also known as Maryland Heights, and Blue Ridge Mountain
, which forms the border between West Virginia and Virginia, to the south. The second set of ridges is South Mountain
in Maryland and Short Hill Mountain
in Virginia. US 340 passes along the northern edge of Blue Ridge Mountain then passes through the northwestern corner of Loudoun County, Virginia
before crossing the Potomac River at an angle, running southwest–northeast on a two-lane steel continuous deck truss bridge at the community of Sandy Hook. On the Maryland side, the bridge also crosses the Chesapeake and Ohio Canal
, CSX
's Cumberland Subdivision
, and Sandy Hook Road, the original alignment of US 340.
Just north of the bridge, US 340 is named Jefferson Pike and widens to a two-lane divided highway that intersects Valley Road and Keep Tryst Road; the sweeping ramp from northbound US 340 to Keep Tryst Road is the old alignment of US 340. Beyond the intersection, the U.S. highway curves to the east, expands to four lanes, and meets the southern end of MD 67 (Rohrersville Road) at a trumpet interchange in Weverton
. After the highway crosses Israel Creek, the eastbound direction of US 340 has a right-in/right-out
intersection with the eastern end of Keep Tryst Road. The U.S. highway becomes a freeway with a speed limit of 65 miles per hour (104.6 km/h) that parallels the C&O Canal and the railroad line, now part of the Metropolitan Subdivision, between the river and the southern end of South Mountain into Frederick County, where US 340's name changes to Jefferson National Pike and the highway meets the western end of MD 180 (Jefferson Pike) at a partial interchange near Knoxville. There is no access from westbound US 340 to eastbound MD 180 or from westbound MD 180 to eastbound US 340.
US 340 veers away from the Potomac River and passes through farmland of the Catoctin Valley, paralleled by its old alignment, MD 180, at a distance to the south. The U.S. highway meets MD 17 (Burkittsville Road) at a diamond interchange near Rosemont
and crosses Little Catoctin Creek. East of Petersville, US 340 has a diamond interchange with MD 180 and crosses Catoctin Creek
. On the western edge of Jefferson, westbound US 340 receives a ramp from MD 180. Full access to Jefferson is provided by a diamond interchange with Lander Road. The U.S. highway passes through a wide gap in Catoctin Mountain
and has a partial interchange with US 15 (Catoctin Mountain Highway), which heads south toward Point of Rocks. US 15 and US 340 join in a concurrency that lasts through US 340's eastern terminus in Frederick. Access from northbound US 15 to westbound US 340 and from eastbound US 340 to southbound US 15 is provided through performing a U-turn at the next interchange, a diamond interchange with Mt. Zion Road.
US 340 and US 15 cross over Ballenger Creek
and the freeway's speed limit drops to 55 miles per hour (88.5 km/h) before the highways approach a series of three interchanges on the southwest side of Frederick. The highway's partial interchange with I-70 (Eisenhower Memorial Highway) features ramps from eastbound I-70 to both directions of US 340, a ramp from westbound I-70 to westbound US 340, and a ramp from eastbound US 340 to eastbound I-70 and access to southbound I-270 just to the east. Immediately to the northeast, US 15 and US 340 have a folded diamond interchange with MD 180 and MD 351, which meets MD 180 just south of the interchange, that features four loop ramps. US 340 reaches its eastern terminus at the third interchange, which is a partial cloverleaf interchange with the Frederick Freeway. The first ramp from eastbound US 340 provides access to westbound I-70; the second ramp leads to the northbound Frederick Freeway (US 40), onto which US 15 exits. The ramps from westbound US 340 provide full access to I-70, I-270, US 15, and US 40. The roadway continues northeast as Jefferson Street, which reduces to a two-lane undivided street that heads toward an intersection with MD 144 (South Street eastbound and Patrick Street westbound) just west of downtown Frederick. The portion of Jefferson Street between the overpass of US 40 and just west of Jefferson Street's intersection with Pearl Street is unsigned US 15B.
US 340 was widened and resurfaced with bituminous concrete from Knoxville to the approach to new bridge at Sandy Hook in 1948. In conjunction with the construction of the Frederick Freeway, US 340's cloverleaf interchange with US 40 was built in 1954 and 1955. Jefferson Street in Frederick was widened in 1956. When US 40 was moved from Patrick Street to the Frederick Freeway in 1959, US 340's eastern terminus was moved from Patrick Street west to the new interchange. Construction on the US 340 freeway began when the highway's bridge across Catoctin Creek was built in 1961. This bridge came into use in 1964 when the freeway segment between the MD 180 interchange east of Petersville and the ramp from MD 180 west of Jefferson was opened, replacing the curvaceous old alignment at Catoctin Creek. The present alignment of US 340 opened as a four-lane divided highway from the Valley Road / Keep Tryst Road intersection in Sandy Hook east to Weverton also opened that year. The portion of the freeway between Weverton and MD 180 east of Petersville was under construction in 1964 and completed in 1965. MD 180 was assigned to old US 340 from Sandy Hook to west of Jefferson in 1965.
Construction on the US 340 freeway east toward Frederick began in 1966. The freeway east to the current Point of Rocks – Jefferson segment of US 15 was completed in 1967; however, the US 15 interchange would not become operational until the new US 15 was completed and the two U.S. highways became concurrent in 1970. US 340's interchanges with I-70 and MD 180 were completed in 1968 and the portion of the freeway from the US 15 interchange east to MD 180 opened in 1969. At that time, MD 180 was extended east over the old Jefferson–Frederick section of US 340. US 340's interchanges with MD 67 in Weverton and Mt. Zion Road near Frederick opened in 1971 and 1972, respectively. Several ramps were added to improve access between US 340 and I-70 in 1997, including a pair of ramps from eastbound I-70 to US 340 and the connection from northbound US 340 to westbound I-70 at US 340's northern terminus. The interchange at US 340's northern terminus was converted from a cloverleaf interchange to a partial cloverleaf interchange with traffic signals in 2004.
—one for CSX's Cumberland Subdivision on the north and the other for the Shenandoah Subdivision
—that presently cross the river at the site. After the highway bridge was destroyed in the March 1936 flood, a wooden floor was placed on the Shenandoah Subdivision bridge for that bridge to temporarily serve both rail and automobile traffic. Later in 1936, Maryland and West Virginia acquired the right-of-way of the destroyed toll bridge owned by the Harpers Ferry and Potomac Bridge Company by eminent domain with an aim to build a new bridge at the site.
In August 1939, Maryland, West Virginia, and Virginia decided to instead embark on a tri-state road and bridge program to replace the destroyed bridge. Plans for bridges across the Potomac and Shenandoah rivers and connecting highways were completed in August 1940. The new bridge across the Potomac river was to be placed at Sandy Hook to exploit the scenic views of the Potomac Water Gap. However, in December 1940, construction was delayed and plans needed to be modified to eliminate a sharp turn at the Virginia landing of the bridge. Despite a late request from the Virginia State Highway Department
to move the Potomac River crossing upstream in June 1941, the concrete substructure of the Sandy Hook bridge was started in autumn 1941. The substructure was completed in March 1943. A request for bids for the Sandy Hook bridge's steel superstructure was advertised in November 1941. However, with the U.S. entering into World War II the following month, the construction of the superstructure of the bridge would be delayed until after the war due to the unavailability of steel.
The Maryland State Roads Commission advertised for bids for the Sandy Hook bridge's superstructure in December 1945. Construction started shortly thereafter and the superstructure was completed in January 1947. The Maryland and Virginia approach roads were completed later in 1947 and the bridge officially opened October 19, 1947. Although the residents of Harpers Ferry lobbied for an on-site replacement of the bridge over the Shenandoah River at Harpers Ferry so US 340 would continue to pass directly through the historic town, the West Virginia State Road Commission completed a new roadway and a new Shenandoah River crossing along US 340's present alignment in 1949. US 340 was rerouted onto its present course over the two new bridges by 1950.
!County
!Location
!Mile
!Exit
!Destinations
!Notes
|-
|rowspan=4|Washington
|rowspan=2|Sandy Hook
|0.00
|
|
|Southern terminus; Virginia
state line at Potomac River
|-
|0.74
|
|Valley Road north / Keep Tryst Road east
|At-grade intersection
|-
|rowspan=2|Weverton
|1.56
|
|
|Trumpet interchange
|-
|1.82
|
|Keep Tryst Road west
|Right-in/right-out
intersection with eastbound US 340
|-2.27
|rowspan=9|Frederick
|Knoxville
|2.53
|
|
|Eastbound exit, westbound entrance
|-
|Rosemont
|4.39
|2
|
|
|-
|Petersville
|7.77
|4
|
|
|-
|rowspan=2|Jefferson
|10.57
|8
|Lander Road – Jefferson
|
|-
|12.30
|
|
|West end of concurrency with US 15; westbound exit, eastbound entrance
|-
|
|13.92
|
|Mt. Zion Road
|
|-
|rowspan=3|Frederick
|16.38
|10
|
|I-70 Exit 52; no exit westbound
|-
|16.62
|11
|
|
|-
|17.01
|12
|
|Northern terminus of US 340; partial cloverleaf interchange; split into exits 12A (I-70) and 12B (US 15 / US 40) eastbound
Greenville, Virginia
Greenville is a census-designated place in Augusta County, Virginia, United States. The population was 886 at the 2000 census. It is part of the Staunton–Waynesboro Micropolitan Statistical Area.-History:...
to Frederick, Maryland
Frederick, Maryland
Frederick is a city in north-central Maryland. It is the county seat of Frederick County, the largest county by area in the state of Maryland. Frederick is an outlying community of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area, which is part of a greater...
. In Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, the U.S. highway runs 17.01 miles (27.4 km) from the Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
state line at the Potomac River
Potomac River
The Potomac River flows into the Chesapeake Bay, located along the mid-Atlantic coast of the United States. The river is approximately long, with a drainage area of about 14,700 square miles...
at Sandy Hook
Sandy Hook, Maryland
Sandy Hook is an unincorporated community in Washington County, Maryland, United States.-References:...
east to its northern terminus at US 15
U.S. Route 15 in Maryland
U.S. Route 15 is a part of the U.S. Highway System that runs from Walterboro, South Carolina to Painted Post, New York. In Maryland, the highway runs from the Virginia state line at the Potomac River in Point of Rocks north to the Pennsylvania state line near Emmitsburg. US 15 is...
and US 40
U.S. Route 40 in Maryland
U.S. Route 40 in the U.S. state of Maryland runs from western Maryland to Cecil County in the state's northeastern corner. With a total length of over , it is the longest numbered highway in Maryland. Almost half of the road overlaps with Interstate 68 or Interstate 70, while the old alignment...
in Frederick. US 340, which is known for most of its length as Jefferson National Pike, connects Frederick with the communities of Jefferson
Jefferson, Maryland
Jefferson is an unincorporated community located in Frederick County, Maryland, established in 1774, incorporated as a town in 1831. However, a year later, in 1832, the citizens of the town decided that municipal government was unnecessary, thus, it was disincorporated.- History of Jefferson...
, Brunswick
Brunswick, Maryland
Brunswick is a city in Frederick County, Maryland, United States. The population was 5,870 at the 2010 census.- History :The area now known as Brunswick was originally home to the Susquehanna Indians. In 1728 the first settlement was built, and the region became known as Eel Town, because the...
, and Knoxville
Knoxville, Maryland
Knoxville is an unincorporated community in Washington County, Maryland, United States.-References:...
in the southern part of the Middletown Valley
Middletown Valley
Middletown Valley, also historically known as Catoctin Valley, is a valley in western Frederick County in the state of Maryland.-Geography:...
of western Frederick County
Frederick County, Maryland
Frederick County is a county located in the western part of the U.S. state of Maryland, bordering the southern border of Pennsylvania and the northeastern border of Virginia. As of the 2010 Census, the population was 233,385....
and Weverton
Weverton, Maryland
Weverton is an unincorporated hamlet located in the southern tip of Washington County, Maryland, near the north shore of the Potomac River. Its population is approximately 500. Weverton is located at the intersection of MD Route 67 and U.S. Route 340...
in far southern Washington County
Washington County, Maryland
Washington County is a county located in the western part of the U.S. state of Maryland, bordering southern Pennsylvania to the north, northern Virginia to the south, and the Eastern Panhandle of West Virginia to the south and west. As of the 2010 Census, its population is 147,430...
. The U.S. highway also links Frederick with Harpers Ferry
Harpers Ferry, West Virginia
Harpers Ferry is a historic town in Jefferson County, West Virginia, United States. In many books the town is called "Harper's Ferry" with an apostrophe....
and Charles Town
Charles Town, West Virginia
Charles Town is a city in and the county seat of Jefferson County, West Virginia, United States. The population was 2,907 at the 2000 census. Due to its similar name, travelers have sometimes confused this city with the state's capital, Charleston.-History:...
in the Eastern Panhandle of West Virginia
Eastern Panhandle of West Virginia
The Eastern Panhandle of West Virginia is a narrow stretch of territory in the northeast of the state, bordering Maryland and Virginia, United States. The Eastern Panhandle Board of Realtors and other local civic organizations consider only the three Easternmost counties, Jefferson, Berkeley and...
. US 340 is a part of the National Highway System
National Highway System (United States)
The National Highway System is a network of strategic highways within the United States, including the Interstate Highway System and other roads serving major airports, ports, rail or truck terminals, railway stations, pipeline terminals and other strategic transport facilities.Individual states...
for its entire length in Maryland.
US 340 was one of the original state roads designated by the Maryland State Roads Commission
Maryland State Highway Administration
The Maryland State Highway Administration is the state agency responsible for maintaining Maryland numbered highways outside of Baltimore City...
. The state road was constructed from Frederick to Knoxville in the early 1910s and completed to Harpers Ferry in 1919. The highway was designated Maryland's portion of US 340 in 1926. US 340 originally crossed the Potomac River at Harpers Ferry; however, the U.S. highway's bridge was destroyed by a flood in 1936. The modern US 340 Bridge was constructed at Sandy Hook between 1940 and 1947, with a long interruption due to World War II. The U.S. highway's freeway between Weverton and Frederick was constructed in the 1960s. Old sections of US 340 became part of Maryland Route 180
Maryland Route 180
Maryland Route 180 is a state highway in the U.S. state of Maryland. Known for most of its length as Jefferson Pike, the state highway runs from U.S. Route 340 in Knoxville east to MD 351 and Interstate 70 in Frederick. MD 180 is the old alignment of US 340 through Knoxville, Petersville, and...
(MD 180).
Route description
US 340 enters Maryland at the Potomac Water GapPotomac Water Gap
The Potomac Water Gap is a double water gap in the Blue Ridge Mountains, located at the intersection of the states of Virginia, West Virginia and Maryland, near Harpers Ferry...
just south of the confluence of the Potomac River and the Shenandoah River
Shenandoah River
The Shenandoah River is a tributary of the Potomac River, long with two forks approximately long each, in the U.S. states of Virginia and West Virginia...
at Harpers Ferry. The Potomac Water Gap is where the Potomac River passes between two sets of ridges. The first set of ridges is Elk Ridge
Elk Ridge (Maryland)
Elk Ridge is a mountain ridge of the Blue Ridge Mountains in Maryland. The ridge is located to the west of South Mountain and runs roughly parallel to it from Rohrersville, in the north, to the Potomac River across from Harpers Ferry, West Virginia, in the south. Across the Potomac the ridge...
to the north, also known as Maryland Heights, and Blue Ridge Mountain
Blue Ridge Mountain
Blue Ridge Mountain, also known as Blue Mountain, is the colloquial name of the western most ridge of the Blue Ridge Mountains in northern Virginia and the Eastern Panhandle of West Virginia...
, which forms the border between West Virginia and Virginia, to the south. The second set of ridges is South Mountain
South Mountain (Maryland and Pennsylvania)
South Mountain is the northern extension of the Blue Ridge Mountain range in Maryland and Pennsylvania. From the Potomac River near Knoxville, Maryland in the south, to Dillsburg, Pennsylvania in the north, the long range separates the Hagerstown and Cumberland valleys from the Piedmont regions of...
in Maryland and Short Hill Mountain
Short Hill Mountain
Short Hill Mountain is a mountain ridge of the Blue Ridge Mountains in northwest Loudoun County, Virginia.- Geography :Short Hill rises sharply from the Piedmont countryside of the Loudoun Valley, northwest of Purcellville, as a low-lying ridge barely over above the surrounding area...
in Virginia. US 340 passes along the northern edge of Blue Ridge Mountain then passes through the northwestern corner of Loudoun County, Virginia
Loudoun County, Virginia
Loudoun County is a county located in the Commonwealth of Virginia, and is part of the Washington Metropolitan Area. As of the 2010 U.S. Census, the county is estimated to be home to 312,311 people, an 84 percent increase over the 2000 figure of 169,599. That increase makes the county the fourth...
before crossing the Potomac River at an angle, running southwest–northeast on a two-lane steel continuous deck truss bridge at the community of Sandy Hook. On the Maryland side, the bridge also crosses the Chesapeake and Ohio Canal
Chesapeake and Ohio Canal
The Chesapeake and Ohio Canal, abbreviated as the C&O Canal, and occasionally referred to as the "Grand Old Ditch," operated from 1831 until 1924 parallel to the Potomac River in Maryland from Cumberland, Maryland to Washington, D.C. The total length of the canal is about . The elevation change of...
, CSX
CSX Transportation
CSX Transportation operates a Class I railroad in the United States known as the CSX Railroad. It is the main subsidiary of the CSX Corporation. The company is headquartered in Jacksonville, Florida, and owns approximately 21,000 route miles...
's Cumberland Subdivision
Cumberland Subdivision
The Cumberland Subdivision is a railroad line owned and operated by CSX Transportation in the U.S. states of Maryland and West Virginia. The line runs from Weverton, Maryland west to near Cumberland, Maryland along the old Baltimore and Ohio Rail Road main line...
, and Sandy Hook Road, the original alignment of US 340.
Just north of the bridge, US 340 is named Jefferson Pike and widens to a two-lane divided highway that intersects Valley Road and Keep Tryst Road; the sweeping ramp from northbound US 340 to Keep Tryst Road is the old alignment of US 340. Beyond the intersection, the U.S. highway curves to the east, expands to four lanes, and meets the southern end of MD 67 (Rohrersville Road) at a trumpet interchange in Weverton
Weverton, Maryland
Weverton is an unincorporated hamlet located in the southern tip of Washington County, Maryland, near the north shore of the Potomac River. Its population is approximately 500. Weverton is located at the intersection of MD Route 67 and U.S. Route 340...
. After the highway crosses Israel Creek, the eastbound direction of US 340 has a right-in/right-out
Right-in/right-out
Right-in/right-out and left-in/left-out refer to a type of road intersection where turning movements of vehicles are restricted. A RIRO permits only right turns and a LILO permits only left turns. RIRO is usual where vehicles drive on the right, and LILO is usual where vehicles drive on the left...
intersection with the eastern end of Keep Tryst Road. The U.S. highway becomes a freeway with a speed limit of 65 miles per hour (104.6 km/h) that parallels the C&O Canal and the railroad line, now part of the Metropolitan Subdivision, between the river and the southern end of South Mountain into Frederick County, where US 340's name changes to Jefferson National Pike and the highway meets the western end of MD 180 (Jefferson Pike) at a partial interchange near Knoxville. There is no access from westbound US 340 to eastbound MD 180 or from westbound MD 180 to eastbound US 340.
US 340 veers away from the Potomac River and passes through farmland of the Catoctin Valley, paralleled by its old alignment, MD 180, at a distance to the south. The U.S. highway meets MD 17 (Burkittsville Road) at a diamond interchange near Rosemont
Rosemont, Maryland
Rosemont is a village in Frederick County, Maryland, United States. The population was 273 at the 2000 census.-Geography:Rosemont is located at ....
and crosses Little Catoctin Creek. East of Petersville, US 340 has a diamond interchange with MD 180 and crosses Catoctin Creek
Catoctin Creek (Maryland)
Catoctin Creek is a tributary of the Potomac River in Frederick County, Maryland, USA. Its source is formed in the Myersville, MD area and flows directly south for the entire length of the stream. Catoctin Creek enters the Potomac River east of Brunswick. The stream flows through Catoctin Creek...
. On the western edge of Jefferson, westbound US 340 receives a ramp from MD 180. Full access to Jefferson is provided by a diamond interchange with Lander Road. The U.S. highway passes through a wide gap in Catoctin Mountain
Catoctin Mountain
Catoctin Mountain, along with the geologically associated Bull Run Mountains, comprises the easternmost mountain ridge of the Blue Ridge Mountains, which are in turn a part of the Appalachian Mountains range...
and has a partial interchange with US 15 (Catoctin Mountain Highway), which heads south toward Point of Rocks. US 15 and US 340 join in a concurrency that lasts through US 340's eastern terminus in Frederick. Access from northbound US 15 to westbound US 340 and from eastbound US 340 to southbound US 15 is provided through performing a U-turn at the next interchange, a diamond interchange with Mt. Zion Road.
US 340 and US 15 cross over Ballenger Creek
Ballenger Creek
Ballenger Creek is a tributary of the Monocacy River in Frederick County, Maryland. The headwaters of the creek are located on the east slope of Catoctin Mountain, about west of the city of Frederick. The stream runs roughly southeast to the Monocacy National Battlefield and the confluence with...
and the freeway's speed limit drops to 55 miles per hour (88.5 km/h) before the highways approach a series of three interchanges on the southwest side of Frederick. The highway's partial interchange with I-70 (Eisenhower Memorial Highway) features ramps from eastbound I-70 to both directions of US 340, a ramp from westbound I-70 to westbound US 340, and a ramp from eastbound US 340 to eastbound I-70 and access to southbound I-270 just to the east. Immediately to the northeast, US 15 and US 340 have a folded diamond interchange with MD 180 and MD 351, which meets MD 180 just south of the interchange, that features four loop ramps. US 340 reaches its eastern terminus at the third interchange, which is a partial cloverleaf interchange with the Frederick Freeway. The first ramp from eastbound US 340 provides access to westbound I-70; the second ramp leads to the northbound Frederick Freeway (US 40), onto which US 15 exits. The ramps from westbound US 340 provide full access to I-70, I-270, US 15, and US 40. The roadway continues northeast as Jefferson Street, which reduces to a two-lane undivided street that heads toward an intersection with MD 144 (South Street eastbound and Patrick Street westbound) just west of downtown Frederick. The portion of Jefferson Street between the overpass of US 40 and just west of Jefferson Street's intersection with Pearl Street is unsigned US 15B.
History
US 340 follows the corridor of the old road from Frederick to Harpers Ferry, part of which was organized as the Frederick and Jefferson Turnpike between the two towns. This highway became one of the original state roads marked for improvement by the Maryland State Roads Commission in 1909. The commission purchased the right-of-way of the turnpike in 1911 and resurfaced the Frederick–Jefferson highway with a 14 feet (4.3 m) wide macadam surface in 1915. The segments from Jefferson to Petersville and from Petersville to Knoxville were placed under construction in 1911 and completed as a 14 feet (4.3 m) macadam road in 1912. The highway from Knoxville to the Potomac River opposite Harpers Ferry was completed as a concrete road in 1919. The Frederick–Knoxville highway was widened to 17 feet (5.2 m) in width around 1926 and became part of US 340 in 1927. US 340 was widened again, this time to 20 feet (6.1 m) between Frederick and Knoxville, by 1934.US 340 was widened and resurfaced with bituminous concrete from Knoxville to the approach to new bridge at Sandy Hook in 1948. In conjunction with the construction of the Frederick Freeway, US 340's cloverleaf interchange with US 40 was built in 1954 and 1955. Jefferson Street in Frederick was widened in 1956. When US 40 was moved from Patrick Street to the Frederick Freeway in 1959, US 340's eastern terminus was moved from Patrick Street west to the new interchange. Construction on the US 340 freeway began when the highway's bridge across Catoctin Creek was built in 1961. This bridge came into use in 1964 when the freeway segment between the MD 180 interchange east of Petersville and the ramp from MD 180 west of Jefferson was opened, replacing the curvaceous old alignment at Catoctin Creek. The present alignment of US 340 opened as a four-lane divided highway from the Valley Road / Keep Tryst Road intersection in Sandy Hook east to Weverton also opened that year. The portion of the freeway between Weverton and MD 180 east of Petersville was under construction in 1964 and completed in 1965. MD 180 was assigned to old US 340 from Sandy Hook to west of Jefferson in 1965.
Construction on the US 340 freeway east toward Frederick began in 1966. The freeway east to the current Point of Rocks – Jefferson segment of US 15 was completed in 1967; however, the US 15 interchange would not become operational until the new US 15 was completed and the two U.S. highways became concurrent in 1970. US 340's interchanges with I-70 and MD 180 were completed in 1968 and the portion of the freeway from the US 15 interchange east to MD 180 opened in 1969. At that time, MD 180 was extended east over the old Jefferson–Frederick section of US 340. US 340's interchanges with MD 67 in Weverton and Mt. Zion Road near Frederick opened in 1971 and 1972, respectively. Several ramps were added to improve access between US 340 and I-70 in 1997, including a pair of ramps from eastbound I-70 to US 340 and the connection from northbound US 340 to westbound I-70 at US 340's northern terminus. The interchange at US 340's northern terminus was converted from a cloverleaf interchange to a partial cloverleaf interchange with traffic signals in 2004.
Sandy Hook Bridge
US 340 originally followed Sandy Hook Road south and west from what is now Keep Tryst Road in Sandy Hook and paralleled the Potomac River west to Maryland Heights directly across the river from downtown Harpers Ferry. There, the U.S. highway crossed the river on a converted railroad bridge immediately upstream from the confluence of the Potomac and Shenandoah rivers and downstream from the two railroad bridgesB & O Railroad Potomac River Crossing
The Baltimore and Ohio Railroad Crossings at the Potomac River are a set of railroad bridges that span the Potomac River between Maryland Heights, Maryland and Harpers Ferry, West Virginia in the United States. Two bridges comprise the current crossing...
—one for CSX's Cumberland Subdivision on the north and the other for the Shenandoah Subdivision
Shenandoah Subdivision
The Shenandoah Subdivision is a railroad line owned and operated by CSX Transportation in the U.S. states of West Virginia and Virginia. The line runs from Harpers Ferry, West Virginia southwest to Strasburg, Virginia along a former Baltimore and Ohio Rail Road line...
—that presently cross the river at the site. After the highway bridge was destroyed in the March 1936 flood, a wooden floor was placed on the Shenandoah Subdivision bridge for that bridge to temporarily serve both rail and automobile traffic. Later in 1936, Maryland and West Virginia acquired the right-of-way of the destroyed toll bridge owned by the Harpers Ferry and Potomac Bridge Company by eminent domain with an aim to build a new bridge at the site.
In August 1939, Maryland, West Virginia, and Virginia decided to instead embark on a tri-state road and bridge program to replace the destroyed bridge. Plans for bridges across the Potomac and Shenandoah rivers and connecting highways were completed in August 1940. The new bridge across the Potomac river was to be placed at Sandy Hook to exploit the scenic views of the Potomac Water Gap. However, in December 1940, construction was delayed and plans needed to be modified to eliminate a sharp turn at the Virginia landing of the bridge. Despite a late request from the Virginia State Highway Department
Virginia Department of Transportation
The Virginia Department of Transportation is the agency of state government responsible for transportation in the state of Virginia in the United States. Headquartered in Downtown Richmond, VDOT is responsible for building, maintaining, and operating the roads, bridges and tunnels in the...
to move the Potomac River crossing upstream in June 1941, the concrete substructure of the Sandy Hook bridge was started in autumn 1941. The substructure was completed in March 1943. A request for bids for the Sandy Hook bridge's steel superstructure was advertised in November 1941. However, with the U.S. entering into World War II the following month, the construction of the superstructure of the bridge would be delayed until after the war due to the unavailability of steel.
The Maryland State Roads Commission advertised for bids for the Sandy Hook bridge's superstructure in December 1945. Construction started shortly thereafter and the superstructure was completed in January 1947. The Maryland and Virginia approach roads were completed later in 1947 and the bridge officially opened October 19, 1947. Although the residents of Harpers Ferry lobbied for an on-site replacement of the bridge over the Shenandoah River at Harpers Ferry so US 340 would continue to pass directly through the historic town, the West Virginia State Road Commission completed a new roadway and a new Shenandoah River crossing along US 340's present alignment in 1949. US 340 was rerouted onto its present course over the two new bridges by 1950.
Junction list
{| class=wikitable!County
!Location
!Mile
!Exit
Exit number
An exit number is a number assigned to a road junction, usually an exit from a freeway. It is usually marked on the same sign as the destinations of the exit, as well as a sign in the gore....
!Destinations
!Notes
|-
|rowspan=4|Washington
Washington County, Maryland
Washington County is a county located in the western part of the U.S. state of Maryland, bordering southern Pennsylvania to the north, northern Virginia to the south, and the Eastern Panhandle of West Virginia to the south and west. As of the 2010 Census, its population is 147,430...
|rowspan=2|Sandy Hook
Sandy Hook, Maryland
Sandy Hook is an unincorporated community in Washington County, Maryland, United States.-References:...
|0.00
|
|
|Southern terminus; Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
state line at Potomac River
Potomac River
The Potomac River flows into the Chesapeake Bay, located along the mid-Atlantic coast of the United States. The river is approximately long, with a drainage area of about 14,700 square miles...
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|0.74
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|Valley Road north / Keep Tryst Road east
|At-grade intersection
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|rowspan=2|Weverton
Weverton, Maryland
Weverton is an unincorporated hamlet located in the southern tip of Washington County, Maryland, near the north shore of the Potomac River. Its population is approximately 500. Weverton is located at the intersection of MD Route 67 and U.S. Route 340...
|1.56
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|Trumpet interchange
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|1.82
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|Keep Tryst Road west
|Right-in/right-out
Right-in/right-out
Right-in/right-out and left-in/left-out refer to a type of road intersection where turning movements of vehicles are restricted. A RIRO permits only right turns and a LILO permits only left turns. RIRO is usual where vehicles drive on the right, and LILO is usual where vehicles drive on the left...
intersection with eastbound US 340
|-2.27
|rowspan=9|Frederick
Frederick County, Maryland
Frederick County is a county located in the western part of the U.S. state of Maryland, bordering the southern border of Pennsylvania and the northeastern border of Virginia. As of the 2010 Census, the population was 233,385....
|Knoxville
Knoxville, Maryland
Knoxville is an unincorporated community in Washington County, Maryland, United States.-References:...
|2.53
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|Eastbound exit, westbound entrance
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|Rosemont
Rosemont, Maryland
Rosemont is a village in Frederick County, Maryland, United States. The population was 273 at the 2000 census.-Geography:Rosemont is located at ....
|4.39
|2
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|Petersville
|7.77
|4
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|rowspan=2|Jefferson
Jefferson, Maryland
Jefferson is an unincorporated community located in Frederick County, Maryland, established in 1774, incorporated as a town in 1831. However, a year later, in 1832, the citizens of the town decided that municipal government was unnecessary, thus, it was disincorporated.- History of Jefferson...
|10.57
|8
|Lander Road – Jefferson
Jefferson, Maryland
Jefferson is an unincorporated community located in Frederick County, Maryland, established in 1774, incorporated as a town in 1831. However, a year later, in 1832, the citizens of the town decided that municipal government was unnecessary, thus, it was disincorporated.- History of Jefferson...
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|12.30
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|West end of concurrency with US 15; westbound exit, eastbound entrance
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|13.92
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|Mt. Zion Road
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|rowspan=3|Frederick
Frederick, Maryland
Frederick is a city in north-central Maryland. It is the county seat of Frederick County, the largest county by area in the state of Maryland. Frederick is an outlying community of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area, which is part of a greater...
|16.38
|10
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|I-70 Exit 52; no exit westbound
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|16.62
|11
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|17.01
|12
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|Northern terminus of US 340; partial cloverleaf interchange; split into exits 12A (I-70) and 12B (US 15 / US 40) eastbound