It has Dakota sandstone concretions much like Rock City, but here most are not nearly as exposed. There could be a great many concretions at this park, but almost all are still covered by the surrounding soil and only a portion is seen. The underlying rock is softer sandstone and is eroding away, but some of it still remains and has been supporting three of the rocks for many years.

The resulting combination of rocks have a mushroom shape.

About 20 miles SW of Salina, Kansas off Highway 140 is Kansas' smallest state park - Mushroom Rock State Park. The 5 acre park is about 2 miles south of the highway on dirt roads that can be very bad after a rain.