It runs along the Mashamoquet Brook State Park before intersecting with Route 169.

It proceeds eastward, soon passing over the Quinebaug River into the town of Killingly.

[2] Route 101 from the western terminus to milepost 6.78 in East Killingly is also known as the Leif Ericson Highway.

Beyond the state line it continued as the Rhode Island and Connecticut Turnpike to Providence.

The turnpike from Phoenixville to west of Pomfret Landing was designated as part of Route 101.

It now began in Canaan and ran through Hartford to Phoenixville, where it continued east along its 1920s alignment.