Two of the five Great Lakes are considered separate lakes, but are actually one lake, separated by the Strait of Mackinac. Together they form the largest of the Great Lakes. Which two lakes are they?

While they have carried separate names for centuries, Lake Michigan and Lake Huron are technically a single hydrological entity. The two are joined by the Straits of Mackinac, a deep and wide channel that is nearly five miles across at its narrowest point. This massive connection allows their waters to mix freely, and as a result, they share the same water level and rise and fall together in a shared basin. Scientists and hydrologists often refer to them collectively as one lake: Lake Michigan-Huron.

The distinction in naming is purely a matter of history. Early European explorers encountered the vast basins from different directions, and from their perspective on the water or land, the large peninsulas of Michigan made them appear as two entirely separate bodies of water. The names were established long before a modern understanding of the Great (Review) Lakes' hydrology, and the convention simply stuck.

When considered as the single body of water they truly are, Lake Michigan-Huron is the largest freshwater lake in the world by surface area, covering a staggering 45,300 square miles. The iconic Mackinac Bridge, which gracefully spans the straits, serves as a constant and beautiful reminder of the connection between these two great, but unified, lakes.