Lake Dennison Recreation Area is a 121-acre (49 ha) Massachusetts state park located in the town of Winchendon. It comprises a small portion of the 4,221 acres (1,708 ha) of the U.S. Army Corps of Engineers' Birch Hill Flood Control Project that are managed by the Department of Conservation and Recreation and that also include Otter River State Forest.

Activities and amenities

• Lake Dennison: The lake offers a swimming beach with restrooms, pavilion, and picnic areas. Fishing and a ramp for non-motorized boating are also available.
• Camping: There are 150 campsites and a dump station.
• Trails: Trails are used for hiking, horseback riding, cross-country skiing, and snowmobiling.
• The park also offers showers, restricted hunting, and interpretive programs.