Lake Winnipesaukee is the largest lake in the U.S. state of New Hampshire, located in the Lakes Region at the foothills of the White Mountains. It is approximately 21 miles long and from 1 to 9 miles wide, covering 69 square miles —71 square miles when Paugus Bay is included—with a maximum depth of 180 feet. The center area of the l…Lake Winnipesaukee is the largest lake in the U.S. state of New Hampshire, located in the Lakes Region at the foothills of the White Mountains. It is approximately 21 miles long and from 1 to 9 miles wide, covering 69 square miles —71 square miles when Paugus Bay is included—with a maximum depth of 180 feet. The center area of the lake is called The Broads.