Mississippi Highway 309 (MS 309) is a two-lane, north–south highway in Marshall County

Marshall County, Mississippi

-Demographics:At the 2000 census, there were 34,993 people, 12,163 households and 9,110 families residing in the county. The population density was 50 per square mile . There were 13,252 housing units at an average density of 19 per square mile...

. It runs from the Mississippi

Mississippi

Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi...

–Tennessee

Tennessee

Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

 state line south through western Marshall County to its southern terminus at MS 4, just east of the community of Chulahoma

Chulahoma, Mississippi

Chulahoma is an unincorporated community in Marshall County in the U.S. state of Mississippi. It is located in the hill country of northern Mississippi.-Culture:...

.

Route description

MS 309's northern terminus lies at the Tennessee state line, continuous with Byhalia Road in Shelby County, Tennessee

Shelby County, Tennessee

Shelby County is a county located in the U.S. state of Tennessee. It is the state's largest both in terms of population and geographic area, with a population of 927,644 at the 2010 census...

, to the north. MS 309 travels south through the junction with MS 302

Mississippi Highway 302

Mississippi Highway 302 is the main east-west highway in DeSoto County, Mississippi, extending into Marshall County, Mississippi to the east. It runs approximately two miles south of the Mississippi/Tennessee state line, from a western terminus at Mississippi Highway 161 in Walls, to U.S...

 at Barton

Barton, Mississippi

Barton is an unincorporated community in western Marshall County, Mississippi, United States. It is located at the intersection of State Highways 302 and 309, at latitude 34.964 and longitude -89.689.-Major Thoroughfares:...

.

Below Barton, MS 309 continues south, crossing the Coldwater River

Coldwater River (Mississippi)

The Coldwater River is a river which flows for through northwestern Mississippi in the United States. It is a tributary of the Tallahatchie River, and part of the watershed of the Mississippi River, via the Yazoo River....

 before entering the town of Byhalia

Byhalia, Mississippi

Byhalia is a town in Marshall County, Mississippi, United States. The population was 706 as of the 2000 census.-Geography:According to the United States Census Bureau, the town has a total area of , all of it land.-History:...

; where the highway passes through a grade-separated

Grade separation

Grade separation is the method of aligning a junction of two or more transport axes at different heights so that they will not disrupt the traffic flow on other transit routes when they cross each other. The composition of such transport axes does not have to be uniform; it can consist of a...

 interchange with U.S. Route 78

U.S. Route 78

U.S. Highway 78 is an east–west United States highway that runs for 715 miles from Memphis, Tennessee, to Charleston, South Carolina. Between Memphis and Birmingham, Alabama, it is being upgraded to become Interstate 22....

 (US 78). Thence, MS 309 continues to its southern terminus at MS 4, just east of the community of Chulahoma.