According to the United States Census Bureau, the town has a total area of 37.86 square miles (98.06 km2), of which, 37.52 square miles (97.18 km2) of it is land and 0.34 square miles (0.88 km2) is water. Berwick is drained by the Little River and Salmon Falls River. Diamond Hill, elevation 490 feet (149.4 m) above sea level, is the town's highest point. The lowest elevation, which is approximately 70 feet (21.3 m) above sea level, is on the Salmon River as it crosses the southern most town border with South Berwick.
|Cities and towns (E)|
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