The Inner is at the tip of Lynde Point, Fenwick's peninsula, and the Outer is a quarter mile off shore, connected by a rough jetty.

Frequent features include gable-on-hip roofs that encompass side porches with minimalist wood bracing, creating a sense of heaviness characteristic of the Shingle style.

[4]: 13  All of the three are typified in St. Mary's-By-the-Sea, a 1 and 1/2 story church building at 30 Agawam Avenue, designed by Francis Goodwin and built in 1883.

[4]: 7, 13 In the late 1800s The Fenwick Golf Course was created from several empty lots in the center of the district and is the site of the Stephen Potter Cup.

The 9-hole golf course has changed layouts on several occasions, with the most recent re-design in the 1930s following acquisition of the course by the British manufacturer Armitage Shanks.

Fenwick is in the southeastern corner of Middlesex County and is bordered to the east by the Connecticut River and the south by Long Island Sound.

The main road is CT 154, which goes over the bay on the north side of the borough and leads 2.5 miles (4.0 km) to Old Saybrook Center.