- Western Terminus:
- Madison-Durham Road (CT 79) in Killingworth
- Eastern Terminus:
- Town Street (CT 82) and Norwich-Salem Road (CT 82) in Hadlyme
- 16.35 miles
- Middlesex, New London
CT 148 is an east/west route from Killingworth to Hadlyme. It is divided into two sections, one on each side of the Connecticut River. A ferry connects the two sections during the summer months. CT 148 begins at Madison-Durham Road (CT 79) and ends at Town Street (CT 82) and Norwich-Salem Road (CT 82). The entire length is a two-lane undivided road.