Bomoseen Lake is a freshwater lake in the western part of the U.S. state of Vermont. At 12 km (7.5 miles) long and 2.4 km (1.5 miles) wide, it is the largest lake in Vermont that is completely within the state borders (Lake Champlain, though far larger, is shared with New York to the west and Quebec to the north). The lake is south of the Lake Champlain valley and is surronded by the wooded hills of the Taconic Mountains. It is a popular summer resort. Bomoseen State Park and Half Moon State Park are nearby.