Region One is in the northeastern corner of the United States, bordered by the Atlantic Ocean, Canada and the State of New York, consisting of the following states; Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut.

The longest river in the region is the Connecticut River, which flows from northeastern New Hampshire for 655 km (407 mi), emptying into the Long Island Sound, roughly bisecting the region.  Lake Champlain is the largest lake in the region (between Vermont and New York), followed by Moosehead Lake in Maine and Lake Winnipesaukee in New Hampshire.