Hanging Rock is a rare natural feature in the generally level topography of northern Indiana. Situated on the bank of the Wabash River, Hanging Rock contains a portion of a Silurian coral reef and is approximately 420 million years old. It was formed when Indiana and much of the Midwest was covered by a warm, shallow sea. When the river undercut the rock, the top of the rock, 65 feet above the Wabash Valley, was left overhanging its base — thus the preserve’s name. This short trail loops around Hanging Rock’s 200-foot-wide base.
During prehistoric and historic times, humans have used Hanging Rock for navigation, astronomical observation and military observation. The Miami and other indigenous peoples and European Americans have used Hanging Rock as both an overlook and a landmark.
In 2022, ACRES helped the National Park Service celebrate 60 years of recognizing and encouraging the conservation of America’s natural heritage through the National Natural Landmarks Program by making this short video about Hanging Rock: