New Jersey Route 31 - Route Description - Hunterdon County

Hunterdon County

Upon crossing County Route 518, Route 31 enters East Amwell Township, Hunterdon County and continues through areas of farm fields and woods with intermittent residences and businesses. The route eventually forms the border between East Amwell Township and West Amwell Township and intersects County Route 579 (Harbourton Road). The two routes run concurrent to the northwest, becoming a three-lane road with a center left-turn lane that crosses entirely into East Amwell Township before resuming along the border of East and West Amwell Townships. The road becomes a divided highway and crosses entirely into East Amwell Township again before it comes to an interchange with U.S. Route 202, where County Route 579 continues north into Ringoes and Route 31 heads north along U.S. Route 202, a four-lane, divided highway with intersections featuring jughandle ramps.

U.S. Route 202 and Route 31 head to the north, coming to an intersection with Old York Road, which heads to the southwest as Route 179 and to the northeast as County Route 514. Past this intersection, the road forms the border between East Amwell Township to the west and Raritan Township to the east before crossing entirely into Raritan Township. The road continues north through farms, reaching commercial development as it approaches the Flemington area. Past an intersection with County Route 611 (South Main Street), the road widens to six lanes and crosses into Flemington. The road comes to the Flemington Circle where U.S. Route 202 continues to the northeast, Route 12 heads to the west, and Route 31 continues to the north on a five-lane, undivided road.

The route crosses back into Raritan Township, where it briefly becomes a four-lane divided highway before reentering Flemington. Not long afterward, it heads into Raritan Township again, where it crosses County Route 523 (Walter E. Foran Boulevard) and passes by the former site of Flemington Speedway, now a commercial development called Raritan Town Square. Route 31 passes through suburban development before turning into a four-lane, divided highway with some intersections controlled by jughandles and crossing over the South Branch Raritan River into Readington Township. It continues north through a mix of farms and wooded areas with some residential areas, crossing into Clinton Township.

Route 31 comes to an interchange with Interstate 78 and U.S. Route 22, where it turns to the northwest into a more developed setting and interchanges with Route 173. The road runs through Clinton Town, where it crosses the South Branch Raritan River again. Back in Clinton Township, Route 31 intersects County Route 513 (Halstead Street), forming a concurrency with that route and running along the eastern shore of Spruce Run Reservoir. County Route 513 splits from Route 31 by heading north on West Main Street and Route 31 continues north, narrowing to a two-lane undivided road. The route crosses into Lebanon Township, where it heads northwest across the wooded Musconetcong Mountains. Route 31 passes through Glen Gardner, which it enters upon crossing Sprunce Run, before heading into Hampton, where it heads west through that community as a three-lane road with two southbound lanes and one northbound lane.