Arch Rock is a geologic formation on Mackinac Island

Mackinac Island

Mackinac Island is an island and resort area covering in land area, part of the U.S. state of Michigan. It is located in Lake Huron, at the eastern end of the Straits of Mackinac, between the state's Upper and Lower Peninsulas. The island was home to a Native American settlement before European...

 in Michigan

Michigan

Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....

. It is a natural limestone arch

Natural arch

A natural arch or natural bridge is a natural geological formation where a rock arch forms, with an opening underneath. Most natural arches form as a narrow ridge, walled by cliffs, become narrower from erosion, with a softer rock stratum under the cliff-forming stratum gradually eroding out until...

 formed during the Nipissing post-glacial period, a period of high Lake Huron

Lake Huron

Lake Huron is one of the five Great Lakes of North America. Hydrologically, it comprises the larger portion of Lake Michigan-Huron. It is bounded on the east by the Canadian province of Ontario and on the west by the state of Michigan in the United States...

 levels following the end of the Wisconsin glaciation

Wisconsin glaciation

The last glacial period was the most recent glacial period within the current ice age occurring during the last years of the Pleistocene, from approximately 110,000 to 10,000 years ago....

. To this day Arch Rock stands on the Lake Huron shoreline 146 feet (44.5 m) above the water.

Limestone breccia

Breccia

Breccia is a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix, that can be either similar to or different from the composition of the fragments....

 is not an ideal material for natural bridges, and this type of formation is quite rare in the North American Great Lakes

Great Lakes

The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...

 region. The Native Americans saw Arch Rock as a place of numinous

Numinous

Numinous is an English adjective describing the power or presence of a divinity. The word was popularised in the early twentieth century by the German theologian Rudolf Otto in his influential book Das Heilige...

 power, and told many stories and legends about it.

Euro-Americans did not share many of the taboos of their Native predecessors, and treated Arch Rock as a curiosity to be admired. Its presence was a major element in the decisions to create Mackinac National Park

Mackinac National Park

Mackinac National Park was a U.S. national park that existed from 1875 to 1895 on Mackinac Island in northern Michigan making it the second National Park in the United States after Yellowstone National Park in the Rocky Mountains. The 1,044 acre park was created in response to the growing...

 in 1875 and its successor, Mackinac Island State Park

Mackinac Island State Park

Mackinac Island State Park is a state park located on Mackinac Island in the U.S. state of Michigan. The island park encompasses 2.81 mi² , which is approximately 74% of the island's total area of 3.78 mi² . The park is also within the boundaries of the city of Mackinac Island and has permanent...

, in 1895. Arch Rock has been a part of the State Park ever since. Today Arch Rock is a focus of Mackinac Island tourism, and is seen by many visitors to the Island. Several trails and paved roads, including the aptly named Arch Rock Road and Arch Rock Bicycle Trail, lead to the formation.