The Connecticut Lakes are a group of lakes in Coos County, northern New Hampshire, United States, situated along the headwaters of the Connecticut River.
First Connecticut Lake is located in the town of Pittsburg, 11 km northeast of the village center. At 1,243 ha it is the eighth-largest lake located entirely in New Hampshire. It is the lowest in elevation and largest in surface area of the four Connecticut Lakes.
Fish species include landlocked salmon and lake trout.
