Straits of Mackinac Information & Straits of Mackinac Links at HealthHaven.com

The Straits of Mackinac

Located between Michigan's Upper and Lower Peninsulas

The Straits of Mackinac, spanned by the Mackinac Bridge, seen from the southern shore

The Straits of Mackinac is the strip of water that connects two of the Great Lakes, Lake Michigan and Lake Huron, and separates the Lower Peninsula of Michigan from the Upper Peninsula of Michigan. It is a shipping lane connecting, for instance, the steel mills of Gary, Indiana to the iron mines of Minnesota. Before the railroads reached Chicago from the east, it served as part of the path for immigrants into the Midwest and Great Plains. It is five miles (8 km) wide at its narrowest point where it is spanned by the Mackinac Bridge. Before the bridge was built, car ferries were used to cross the straits. Today passenger-only ferries carry people to Mackinac Island which does not permit cars, while passengers can take a vehicle ferry to Bois Blanc Island. Before icebreakers and year-round shipping on the Lower Great Lakes, the Straits would freeze over in winter.

Islands in the Straits of Mackinac include the two populated islands, Bois Blanc Island and Mackinac Island, and the two uninhabited islands, Round Island and St. Helena Island. At 11 miles (18 kilometers) in length, Bois Blanc is by far the largest island in the Straits.

[edit] Geology and history

Satellite photograph of icebreaker paths through the ice in the Straits. The Mackinac Bridge is the vertical line in the center, connecting the landmass of the Upper Peninsula above to lower Michigan below. The icebreaker paths run right-to-left, connecting the open water of Lake Michigan with the open water of Lake Huron between Mackinac Island and Round Island.

The Straits are 5 miles (8.0 km) wide and 120 feet (37 m) deep.^[1] Hydrologically, they do not connect two separate lakes, but rather are a narrow point defining two lobes of a single Lake Michigan-Huron.

The Straits were an important Native American and fur trade route. Located on the southern side of the Straits is the town of Mackinaw City, Michigan, the site of Fort Michilimackinac, a reconstructed French fort founded in 1715, and on the northern side is St. Ignace, Michigan, site of a French Catholic mission to the Indians, founded in 1671. The eastern end of the Straits was controlled by Fort Mackinac on Mackinac Island, a British colonial and early American military base and fur trade center, founded in 1781.

[edit] Straits of Mackinac today

The Straits are patrolled by a detachment of the United States Coast Guard based at Graham Point, St. Ignace. A shipping channel through the winter ice is maintained by the Coast Guard's Great Lakes icebreaker, USCGC Mackinaw, based in Cheboygan, Michigan near the eastern edge of the Straits. This new vessel went into service during the 2005-06 ice season.

Most of the Straits have been set aside by the U.S. state of Michigan as the Straits of Mackinac Shipwreck Preserve, a riparian public space dedicated to those personnel who were lost aboard the boats and ships that sank in these dangerous shipping lanes.

Lighthouses in the Straits of Mackinac include:

The McGulpin Point Light, on McGulpin Point, 3 miles (4.8 km) west of Fort Michilimackinac.
The Old Mackinac Point Light, in Mackinaw City, Michigan, which is open to the public.
The Round Island Light on Round Island, which is not open to the public but which can be viewed from the Mackinac Island ferry channel.
The St. Helena Island Lighthouse, which is not open to the public but is visible from a rest area on U.S. Highway 2 at Gros Cap, Michigan west of St. Ignace, Michigan.
The Bois Blanc Light, which is not open to the public, on the northern shore of Bois Blanc.