Old Lyme is a coastal town in New London County, Connecticut, United States, bounded on the west by the Connecticut River, on the south by the Long Island Sound, on the east by the town of East Lyme, and on the north by the town of Lyme. The town is part of the Lower Connecticut River Valley Planning Region. The main street of the town, Lyme Street, is a historic district with several homes once owned by sea captains. The town has had for many years a thriving art community. Its principal institutions include the Florence Griswold Museum, the Lyme Art Association, and the Lyme Academy of Fine Arts. The town is named after Lyme Regis, England.