Williamsport Falls (Dry Falls) (GM-39)
Scarcely a stone's throw from the courthouse in downtown Williamsport (Warren County) is one of Indiana's highest waterfalls. Small, intermittent Fall Creek tumbles over a ledge of resistant sandstone at the base of the Mansfield Formation. Below this ledge are siltstone and shale of the Borden Group, and weathering of this softer rock causes the falls to slowly recede as the harder cap rock is undermined, and block by block, collapses into the gorge below. Interesting small potholes, scallops, and other features characteristic of abrasive action of water can be seen in the streambed just above the falls.

Williamsport Falls is one of many geologic features that testify to glacial rearrangement of stream patterns. In cutting downward through unconsolidated deposits left behind by the latest glacier, Fall Creek encountered a ridge of resistant sandstone. The course of the creek is now fixed across this ledge, but more easily eroded glacial deposits have been carried away.

Our Hoosier State Beneath Us: Geomorphology