Lake Erie is the fourth-largest lake of the five great lakes in North America and the eleventh-largest globally by surface area. It is also the shallowest and smallest by volume. It is bordered on the north by the Canadian province of Ontario, on the west by the U.S. state of Michigan, on the south and east by the U.S. states of Ohio, Pennsylvania, and New York, and on the southeast by the Niagara River.
The lake is primarily fed by the Detroit River and drains via the Niagara River and the Welland Canal into Lake Ontario. The lake's surface area is approximately 25,744 km², and it has a maximum depth of around 64 metres.
Lake Erie's most abundant fish species by weight is walleye. Besides that, many other species of fish, birds, and various forms of wildlife also inhabit the surrounding areas of Lake Erie.
The name "Erie" is derived from the Iroquoian word erielhonan, meaning "long tail". Among several theories, the most common is that Erie refers to the shape of the lake, which resembles a cat's tail.
Lake Erie's temperature varies seasonally; the warmest surface waters occur in late August when temperatures can reach as high as 29 °C (84 °F), and the coldest occurs in late February and early March, with temperatures sometimes reaching as low as −2 °C (28 °F).
The lake was used for fishing and trading by indigenous peoples prior to European conquest and later became a major navigation route for explorers and traders. Nowadays, it serves as a valuable resource for commerce, transportation, and recreation, including boating, fishing, and tourism. However, Lake Erie has also suffered from industrial pollution in the 20th century, but conservation efforts have greatly improved its water quality in recent decades.