New Hampshire has a well-maintained, well-signed network of Interstate highways, U.S. highways, and state highways. State highway markers still depict the Old Man of the Mountain despite that rock formation’s demise in 2003. Several route numbers align with the same route numbers in neighboring states. State highway numbering does not indicate the highway’s direction. 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
- 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 Canadian 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 Canadian border.
- U.S. 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.
- 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 HamptonBeach and I-95.
New Hampshire has 25 public-use airports, four of which have scheduled commercial passenger service. The busiest airport by number of passengers handled is Manchester-Boston Regional Airport in Manchester and Londonderry, which serves the Greater Boston metropolitan area.
Further information: List of airports in New Hampshire
Long-distance intercity passenger rail service is provided by Amtrak’s Vermonter and Downeaster lines.
As of 2009, Boston-centered MBTA Commuter Rail services reach only as far as northern Massachusetts. The New Hampshire Rail Transit Authority is working to extend “Capital Corridor” service from Lowell, Massachusetts to Nashua, Concord, and Manchester, including Manchester-Boston Regional Airport; and “Coastal Corridor” service from Haverhill, Massachusetts, to Plaistow, New Hampshire. Legislation in 2007 created the New Hampshire Rail Transit Authority (NHRTA) with the goal of overseeing the development of commuter rail in the state of New Hampshire. In 2011, Governor John Lynch vetoed HB 218, a bill passed by Republican lawmakers, which would have drastically curtailed the powers and responsibilities of NHRTA.
Eleven public transit authorities operate local and regional bus services around the state, and eight private carriers operate express bus services which link with the national intercity bus network. The New Hampshire Department of Transportation operates a statewide ride-sharing match service, in addition to independent ride matching and guaranteed ride home programs.
Tourist railroads include the Conway Scenic Railroad, Hobo-Winnipesaukee Railroad, and the Mount Washington Cog Railway.
Freight railways in New Hampshire include Pan Am Railways, the New England Central Railroad, the St. Lawrence and Atlantic Railroad, and New Hampshire Northcoast Corporation.