Who painted those rocks?

The simple answer is God did, but I will add a few details.

The cliffs are pre-Cambrian rock that was once the ocean floor of a tropical sea, and the layers are different sediment accumulations on that open floor. Then the oceans dried up and the glaciers came, carving the rock into these 200 foot cliffs and leaving behind Lake Superior.

Lake Superior is the largest freshwater lake in the world by volume and contains more water than all the other Great Lakes. If you emptied the other four Great Lakes into it, you would need three more Lake Eries to fill it up. It is 400 miles long, 160 miles wide, 1400 feet deep. And chilly. 40 degrees on average. Did I mention blue and clear?

Back to the painted rocks. The rocks are porous and small springs seep from them.  Iron, copper, and various other minerals in the water paint the scene.

Water carves the formations. Superior was balmy the day we took our tour, but when the winds shift from the north, watch out for 8 foot seas. In the winter, ice forms a fairy castle display and further erodes the rock as it thaws.

All this geological history led to a landscape so precious that the US made it into a National Park, one of the must-sees on the Upper Peninsula of Michigan.