New Hampshire has a well-maintained, well-signed and connected network of Interstate highways, U.S. highways, and state highways. Several route numbers align with the same route numbers in neighboring states. State highway numbering is arbitrary, with no overall system as with U.S. and Interstate systems.
Major routes include:
Interstate 89- runs northwest from near Concord to Lebanon on the Vermont border.
Interstate 93- is the main Interstate highway in New Hampshire and runs north from Salem (on the Massachusetts border) to Littleton (on the Vermont border). I-93 connects the more densely populated southern part of the state to the Lakes Region and the White Mountains further to the north.
Interstate 95- runs north–south briefly along New Hampshire’s seacoast to serve the city of Portsmouth, before entering Maine
Major US Highways:
U.S. Route 1 runs north–south briefly along New Hampshire’s seacoast to the east of and paralleling I-95.
U.S. Route 2 runs east–west through Coos County from Maine, intersecting Route 16, skirting the White Mountain National Forest passing through Jefferson and into Vermont.
U.S. Route 3 is the longest numbered route in the state, and the only one to run completely through the state from the Massachusetts border to the Canada–U.S. border. It generally parallels Interstate 93. South of Manchester, it takes a more westerly route through Nashua. North of Franconia Notch, U.S. 3 takes a more easterly route, before terminating at the Canada–U.S. border.
Route 4 terminates at the Portsmouth Traffic Circle and runs east–west across the southern part of the state connecting Durham, Concord, Boscawen and Lebanon.
Major State Route:
New Hampshire Route 16 is a major north–south highway in the eastern part of the state that generally parallels the border with Maine, eventually entering Maine as Maine Route 16. The southernmost portion of NH 16 is a four-lane freeway, co-signed with U.S. Route 4.
New Hampshire Route 101 is a major east–west highway in the southern part of the state that connects Keene with Manchester and the Seacoast region. East of Manchester, NH 101 is a four-lane, limited access highway that runs to Hampton Beach and I-95.
Greyhound, Concord Coach, Vermont Translines and Dartmouth Coach all provide intercity bus connections to and from points in New Hampshire and to long-distance points beyond and in between.