According to the United States Census Bureau, the town has a total area of 20.0 square miles (52 km2), of which 19.6 sq mi (51 km2) is land and 0.4 sq mi (1.0 km2) is water, comprising 1.85% of the town. Exeter is drained by the Exeter River, which feeds the Squamscott River. The highest point in Exeter is 250 feet (76 m) above sea level on Great Hill at the town's southwest corner. Exeter lies fully within the Piscataqua River (Coastal) watershed.

The town's center, defined as a census-designated place (CDP), has a total area of 4.5 square miles (12 km2), of which 4.4 sq mi (11 km2) is land and 0.2 sq mi (0.52 km2) (3.74%) is water. For Kensington room places to stay in Exeter NH Please Visit here http://innbythebandstand.com/rooms-and-suites/kensington-room/