Bois Blanc Island is coterminous with Bois Blanc Township, Mackinac County in the U.S. state of Michigan. The island covers about 34 sq mi (88 km2) and is about 12 miles (19 km) long, 6 miles (9.6 km) wide and has 6 lakes. Bois Blanc is located in Lake Huron southeast of Mackinac Island and almost due north of the city of Cheboygan. Some winters a safe path over the ice is marked by discarded Christmas trees allowing islanders to drive over to the mainland.
"Bois Blanc" is French for "white wood". The name is commonly thought to be a reference to either: (a) the silver birch, or more likely (b) the basswood, called "bois blanc" in other contexts. The basswood's white underbark was extensively used by Native Americans and French-speaking fur traders for cordage, including the sewing up of canoes and the manufacture of webbing for snowshoes. The French Canadian colloquil term for "inner bark" was bois blanc. The Indians themselves had a name for Bois Blanc Island and the meaning is the same as the Canadian name. It was called Wigobiminiss. Wigobi or wicopy signifies "tying bark" or "inner bark". Miniss means "island".
"Boblo" is an English corruption of the French pronunciation of the name. Several islands with the same name dot the Great Lakes, and nearly all are known as "Boblo" or "Bob-lo" by the local populations.
Plaunt Transportation is the sole provider of ferry services for the island. Ferries are sailed daily when the straits are not frozen over from Cheboygan to Pointe Aux Pins.