Originally Posted by Steve Sawyer

Uhhh....yes, but even life-long Michiganders like me confuse which of the entities in the area use which spelling. There's a bridge, two forts, a city, a county, the straits themselves, an ice breaker and an island. Some are spelled "aw" some are spelled "ac" and I've always stumbled over which is which. I think the straits, the island, the bridge are "ac", the city, the ice breaker are "aw", the fort on the island is "ac" but the one on the mainland south of the strait is actually "Michilimackinac"

The organizers of the event themselves can't seem to make up their minds, as you'll see it as both "Zoo-de-Mackinaw" and "Zoo-de-Mackinac". Depending on whether you consider the end-point of the ride to be Mackinaw City (which it is), or Mackinac Island (where the last events of the ride occur - the drinking, dancing, eating and partying), either could be correct, but most just avoid the whole issue and call it the "Zoo-de-Mack"