The Discovery of the Sanilac Petroglyphs 

Written by Tonya Blust | Michigan 101


For three days in September 1881, a fire ravaged much of the Thumb area in Michigan’s Lower Peninsula. The blaze decimated towns throughout four counties and shot so much ash into the air that people in New England observed yellow skies and experienced twilight levels of darkness at noon. The Thumb Fire ultimately burned more than one million acres and took the lives of 282 people.

When the flames died down, residents set to work cleaning and salvaging what remained. As crews examined a rocky surface that vegetation had previously hidden, they encountered an unexpected sight. Carved into the smooth sandstone was a startling array of images: birds, hand prints, abstract swirls and lines and men holding bows.

One of the many pictographs of the Sanilac Petroglyphs. 

The carvings were not the work of a recent artist, as up to that point, foliage had obscured the surface upon which they rested. Researchers investigated and determined that the carvings were at least 300 to 1,000 years old, and were the work of an unknown Native American tribe that lived in the area during the Late Woodland Period. The images, located in Sanilac County, became known as the Sanilac Petroglyphs, and are the only known Native American rock carvings in the state of Michigan.

Although researchers could not determine which tribe had carved the images, we do know a little about the petroglyphs’ carvers based on the era in which they lived. Native Americans who resided in Michigan during the Late Woodland Period (500 to 1650 AD) were hunters who used bows and arrows. (This means they also followed the old adage, “carve what you know.”) Eventually, many of them turned to farming as a means of support, and settled into villages, abandoning their previous nomadic existences as hunters and gatherers.

The images, located in Sanilac County, became known as the Sanilac Petroglyphs, and are the only known Native American rock carvings in the state of Michigan.

Today, the Sanilac Petroglyphs attract thousands of visitors every year and are an excellent resource for tourists interested in the state’s native cultures. Yet this popularity comes at a price. The soft sandstone that made an attractive surface for Native American carvers has left the petroglyphs susceptible to erosion and graffiti from modern-day idiots. (I’m calling a spade a spade here.) However, the state has made efforts to protect the site from future damage, so, with luck (as well as respect from the viewing public), the Sanilac Petroglyphs will be around for years to come.

Facts about the fire:
The 1881 Thumb Fire came on the heels of the Great Fire of 1871, which afflicted towns, villages, and cities across the state. Both fires stemmed from a variety of causes, primary among them the devastation that logging had wreaked on the landscape. Once loggers removed all the trees from an area, they left behind stumps, branches, and unused wood that made perfect fodder for fires. When weather conditions became hot and dry (as they did during the summers of 1871 and 1881), fires started easily and quickly spread across the ravaged landscape.

The Thumb Fire was the first official disaster relief project tackled by the American Red Cross, which Clara Barton had founded that same year.

For more information:
Sanilac Petroglyphs State Park website