Higganum Reservoir State Park is a public recreation area in Haddam, Connecticut, along the shores of Higganum Reservoir. Listed in the 1955 Connecticut Register and Manual as a 75-acre state park, it later grew to 147 acres. The park has remained focused on simple outdoor recreation, offering public access for fishing, hiking, hunting, and car-top boating. Rather than serving as a heavily developed destination, it is significant as a quiet reservoir-side park that preserves access to the water and nearby land for low-key recreational use.