Eroding Sandstone Bluffs

To the south and west lie hundreds of square miles of sandstone and dolomite uplands. These extensive rock layers once overlaid this area, but streams have eroded them away. Today, only isolated remnants of this large upland remain. Mill Bluff is one of these remnants. Mill Bluff owes its existence to a hard sandstone layer called cap rock. This cap rock protects layers of softer sandstone underneath. You can see this soft sandstone eroding from Mill Bluff as you hike this trail. In time, Mill Bluff will erode to the level of the plain around you.

Oakdale, Wisconsin · United States