Bear Creek Canyon and Portland Arch (GM-02)
Bear Creek, flowing to the northwest to join the Wabash River, has cut a deep canyon into a massive Pennsylvanian sandstone, and a series of sharp curves, flood plains, talus slops, and precipitous 90-foot-high cliffs have been formed. Near the downstream end of the canyon a small tributary has cut a tunnel 8 feet high through a narrow backbone ridge of bedrock. This arch-like opening is known as Portland Arch. The area is a dedicated nature preserve under the ownership and management of the Indiana Department of Natural Resources.
Our Hoosier State Beneath Us: Geomorphology