New Hampshire Route 12

New Hampshire Route 12
Map of western New Hampshire with NH 12 highlighted in red
Route information
Maintained by NHDOT
Length:	62.773 mi (101.023 km)
Major junctions
South end:	Route 12 in Winchendon, MA
	NH 9 / NH 10 / NH 101 in Keene
North end:	VT 12 in Ascutney, VT
Location
Counties:	Cheshire, Sullivan
Highway system
New Hampshire Highway System Interstate U.S. State Turnpikes ← NH 11 NH 13 →

New Hampshire Route 12 is a 62.773-mile (101.023 km) long north-south state highway in southwestern New Hampshire. Its southern terminus is at the Massachusetts state line in Fitzwilliam, where it continues south as Massachusetts Route 12. Its northern terminus is at the Vermont state line in Claremont (a terminus it shares with New Hampshire Route 103), where it continues north as Vermont Route 12. Most of the northern part of NH 12 runs along the Connecticut River.

Its number is derived from its original 1922 designation as New England Interstate Route 12 (also known as the "Keene Way"). Present-day Vermont Route 12, New Hampshire Route 12, Massachusetts Route 12 and Connecticut Route 12 still mostly follow the original route. The 283.3-mile (455.9 km) four-state series of State Route 12s extend from Morrisville, Vermont to Groton, Connecticut.

NH 12 begins in Fitzwilliam where it connects to Massachusetts Route 12 at the state line. The highway heads northwest into the town center where it crosses NH 119. NH 12 continues northwest through Troy, then dips into parts of Marlborough and Swanzey before entering the city of Keene. Immediately after crossing into Keene, NH 12 intersects the northern terminus of NH 32 then meets NH 101 near Keene State College. NH 12 turns west along NH 101, then meets NH 10 at a roundabout. NH 10 joins NH 12 and NH 101 west to the next intersection at NH 9. NH 101 ends while NH 10 and NH 12 turn north with NH 9 eastbound in tow. The three routes are multiplexed for 1.2 miles (1.9 km) as they bypass downtown Keene to the west. NH 9 and NH 10 split off at a trumpet interchange while NH 12 continues northwest. The highway interchanges with NH 12A on its way out of town.