New Hampshire Route 18 is a 20.13 miles (32.4 km) long north–south state highway

State highway

State highway, state road or state route can refer to one of three related concepts, two of them related to a state or provincial government in a country that is divided into states or provinces :#A...

 in New Hampshire

New Hampshire

New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...

. Its northern terminus is at the Vermont

Vermont

Vermont is a state in the New England region of the northeastern United States of America. The state ranks 43rd in land area, , and 45th in total area. Its population according to the 2010 census, 630,337, is the second smallest in the country, larger only than Wyoming. It is the only New England...

 state line in the town of Littleton

Littleton, New Hampshire

Littleton is a town in Grafton County, New Hampshire, United States. The population was 5,928 at the 2010 census. Situated at the edge of the White Mountains, Littleton is bounded on the northwest by the Connecticut River....

, where the road continues north as Vermont Route 18

Vermont Route 18

Vermont Route 18 is a state highway in Caledonia County, Vermont, United States. It runs southeast from the town of St. Johnsbury to the New Hampshire state line, continuing there as New Hampshire Route 18...

. The southern terminus of NH 18 is at an interchange with Interstate 93 and U.S. Route 3 in Franconia

Franconia, New Hampshire

Franconia is a town in Grafton County, New Hampshire, United States. The population was 1,104 at the 2010 census. Set in the White Mountains, Franconia is home to the northern half of Franconia Notch State Park. Parts of the White Mountain National Forest are in the eastern and southern portions...

.

Route description

|}

Road names along route

NH Route 18 uses the following local road names:

Franconia

• Profile Road
• Main Street

Bethlehem

• Profile Road/Old Franconia Road
• Main Street/Dartmouth College Road

Littleton

• Bethlehem Road
• Cottage Street
• Main Street
• St. Johnsbury Road