National Michigan Day is observed worldwide every January 18 to celebrate Michigan as the 26th state to join the United States. This day does not mark the actual anniversary of Michigan's admission, which is January 26, but rather honors the state's distinctive history, culture, and heritage. Michigan, known as the Great Lake State, the Wolverine State, and the Mitten State, consists of two peninsulas and borders four of the five Great Lakes. The state's history includes significant events such as its early exploration by the French in the 1620s, its status as part of the Northwest Territory, and its eventual admission to the Union in 1837 after resolving a boundary dispute with Ohio. National Day Calendar introduced National Michigan Day as part of the National State Days project in 2017, which celebrates one state each week throughout the year.