Echo Lake is a 38.2-acre (15.5 ha) water body located in Franconia Notch in the White Mountains of New Hampshire, at the foot of Cannon Mountain. The lake is in the Connecticut River watershed, near the height of land in Franconia Notch; water from the lake's outlet flows north via Lafayette Brook to the Gale River, then the Ammonoosuc River, and finally the Connecticut River to Long Island Sound, an arm of the Atlantic Ocean. The lake is classified as a coldwater fishery, with observed species including brook trout.