Skull Cave is a small and shallow cave on the central heights of 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"....

, USA. The cave was carved during the Algonquin post-glacial period by the waters of Lake Algonquin

Glacial Lake Algonquin

Lake Algonquin was a proglacial lake that existed in east-central North America at the time of the last ice age. Parts of the former lake are now Lake Huron, Georgian Bay and inland portions of northern Michigan....

, a swollen meltwater ancestor of today's 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...

.

Skull Cave is primarily of interest for its historical associations. It is believed to have been used as an inhumation site by Native Americans of the Straits of Mackinac

Straits of Mackinac

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 providing passage for raw materials and finished goods, connecting, for...

 area in the 18th century.

While in active use as a site for human remains, the cave was also used as a refuge in 1763 by fur trader Alexander Henry, a survivor of the capture of Fort Michilimackinac

Fort Michilimackinac

Fort Michilimackinac was an 18th century French, and later British, fort and trading post in the Great Lakes of North America. Built around 1715, it was located along the southern shore of the strategic Straits of Mackinac connecting Lake Huron and Lake Michigan, at the northern tip of the lower...

 by Native Americans allied with Chief Pontiac

Chief Pontiac

Pontiac or Obwandiyag , was an Ottawa leader who became famous for his role in Pontiac's Rebellion , an American Indian struggle against the British military occupation of the Great Lakes region following the British victory in the French and Indian War. Historians disagree about Pontiac's...

. In his "Memoirs," Henry recalled a night spent as a refugee in the bone-strewn cavern.

Henry recalled his ordeal as follows:

On going into the cave, of which the entrance was nearly ten feet wide, I found the further end to be rounded in its shape, like that of an oven, but with a further aperture, too small, however, to be explored. After thus looking around me, I broke small branches from the trees and spread them for a bed, then wrapped myself in my blanket and slept till day-break. On awaking, I felt myself incommoded by some object upon which I lay, and, removing it, found it to be a bone. This I supposed to be that of a deer, or some other animal, and what might very naturally be looked for in the place in which I was; but when daylight visited my chamber I discovered, with some feelings of horror, that I was lying on nothing less than a heap of human bones and skull

Human skull

The human skull is a bony structure, skeleton, that is in the human head and which supports the structures of the face and forms a cavity for the brain.In humans, the adult skull is normally made up of 22 bones...

s, which covered the floor!

Skull Cave is contained within 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...

. It is located 0.4 miles (0.6 km) north of Fort Mackinac

Fort Mackinac

Fort Mackinac is a former American military outpost garrisoned from the late 18th century to the late 19th century near Michilimackinac, Michigan, on Mackinac Island...

 in the island's interior. It was designated as a Michigan Historic Site

Michigan State Historic Preservation Office

The Michigan State Historic Preservation Office is in charge of the listing of historic resources of local, state, and national interest in the U.S. state of Michigan, including buildings, lighthouses, bridges, historic districts, and many other properties deemed important to the history of Michigan...

on January 12, 1959, and granted state historical marker #L0004.