The Finger Lakes are a group of eleven long, narrow, roughly north–south lakes in an area called the Finger Lakes region in New York, in the United States. This region straddles the northern and transitional edge, known as the Finger Lakes Uplands and Gorges ecoregion, of the Northern Allegheny Plateau and the Ontario Lowlands ecoregion of the Great Lakes Lowlands.
The geological term finger lake refers to a long, narrow lake in an overdeepened glacial valley, while the proper name Finger Lakes goes back to the late 19th century. Cayuga and Seneca Lakes are among the deepest in the United States, measuring 435 feet and 618 feet respectively, with bottoms well below sea level. Though none of the lakes' width exceeds 3.5 miles, Seneca Lake is 38.1 miles long, and 66.9 square miles, the largest in total area.