The Hadlyme North Historic District is an 81-acre (33 ha) historic district located in the southwest corner of the town of East Haddam, Connecticut (just north of the town line with Lyme). It represents the historic core of the village of Hadlyme, which straddles the town line, and consists primarily of two north-south roads, Town Street (Route 82 and Old Town Street). The village arose around a church society founded in 1743, and grew with the development of small industries along area waterways. It was listed on the National Register of Historic Places in 1988.