Route 161 is a state highway in southeastern Connecticut, running from the shoreline village of Niantic in East Lyme to the village of Chesterfield in Montville.

It proceeds north for 1.1 miles (1.8 km), curving left then turning right onto Flanders Road.

Route 161 continues north for another 1.8 miles (2.9 km) until it reaches the interchange with I-95 (at exit 74).

In this area, one can access East Lyme High School and the Flanders Shopping Plaza from Route 161.

The road turns northeast for another 1.1 miles (1.8 km) to end at an intersection with Route 85 in the village of Chesterfield.