The Connecticut Lakes are a group of lakes in northern New Hampshire, and form the beginning of the Connecticut River. All of the lakes are technically contained within Pittsburg, New Hampshire, but are far from the town. There are 4 lakes: First Connecticut Lake , Second , Third and Fourth Connecticut Lake. The first Connecticut Lake is the biggest and the fourth is the smallest (and northernmost). All lakes are north of the 45th Parallel. There is a state forest next to them (Connecticut Lakes State Forest ). The lakes can only be accessed by driving north to the terminus of U.S. Highway 3 through New Hampshire or driving south from Quebec.

(Note: There is a trail called the Fourth Connecticut Lake Trail that goes in and out of Canada.)