Glacial Grooves State Memorial
A National Natural Landmark, the Glacial Grooves on the north side of Kelleys Island are the largest easily accessible such grooves in the world and are accessible daily in season, weather-permitting, via ferry. From a walkway, footbridge, and stairs you can look down on the immense grooves, which are 400 ft long, 35 ft wide, and up to 10 ft deep, suggesting the tremendous power of the ice that formed them. Glacial Grooves Geological Preserve contains marine fossils that are 350 to 400 million years old. They were scoured into solid limestone bedrock about 18,000 years ago by the great ice sheet which covered part of North America. Open year-round, dawn-dusk.