(from wikipedia)
Massachusetts Route 10 is a 60.69-mile-long (97.67 km) north–south state highway that runs from the Connecticut state line at Southwick to the New Hampshire state line at Northfield. Originally part of New England Route 10 from 1922 to 1927, it continues to the south as Connecticut Route 10, and to the north as New Hampshire Route 10.
Route 10 crosses the border from Granby, Connecticut into Southwick, Massachusetts, overlapped with U.S. 202. It runs north through the Pioneer Valley towns of Southwick, Westfield, Southampton, Easthampton, Northampton, Hatfield, Whately, Deerfield, Greenfield, Bernardston, Gill, and Northfield. Route 10 has a long concurrency with U.S. 5 for about 25 miles (40 km) from Northampton to Bernardston, where it was sometimes called the "5 & 10 Highway". During this concurrency, it closely parallels Interstate 91, with five exits from Northampton to Deerfield, with close access at Route 2 in Greenfield and another exit, solely for Route 10, in Bernardston. It crosses the Connecticut River in Northfield before entering New Hampshire.
