M-185 to be Open Memorial Day Weekend

M-185, the state highway that encircles Mackinac Island, will be open for guests to travel Memorial Day Weekend. It will remain open through Monday, May 31, and then close for an indefinite amount of time beginning Tuesday, June 1.

Construction to finish paving and securing M-185 after high water and erosion damaged several portions of the roadway is currently underway. The closed section of road will have several large construction vehicles moving throughout it. Barricades will be placed at either end. Going around a barricade is exceedingly dangerous, and people found going around the barricade are subject to a ticket and fine.

The Michigan Department of Transportation (MDOT) is investing about $6 million to rebuild M-185, addressing high-water and wave erosion damage on the shoreline. Roughly 4 miles of the highway around the island (the only state highway in Michigan that does not regularly allow automobile traffic) sustained ongoing damage that escalated in fall 2019 and winter 2020.

The project will repair armor stone along M-185, primarily along the eastern and northern shore of the island from north of Dennis O. Cawthorne Shoreline Trail to British Landing. One location on the western shore, near Devil’s Kitchen, will also be repaired. Work also includes pavement repairs to previously washed out and damaged pavement.

Mackinac State Historic Parks and MDOT will continue to send out releases as more information becomes available on M-185 closures throughout the summer.

Mackinac State Historic Parks, a family of living history museums and parks in northern Michigan’s Straits of Mackinac, is an agency within the Michigan Department of Natural Resources. Its sites—which are accredited by the American Alliance of Museums—include Fort Mackinac, the Biddle House, The Richard and Jane Manoogian Mackinac Art Museum, Historic Downtown Mackinac, and Mackinac Island State Park on Mackinac Island, and Colonial Michilimackinac, Old Mackinac Point Lighthouse, Historic Mill Creek Discovery Park and Michilimackinac State Park in Mackinaw City. Mackinac State Historic Parks is governed by the Mackinac Island State Park Commission, established in 1895 to protect, preserve and present the parks’ rich historic and natural resources for the education and recreation of future generations. Visitor information is available at (231) 436-4100 or online at