1051 Ivy. From W. 1st, 3 miles west and south on K-106, then ½ mile west on Ivy. In this flat fertile Solomon River Valley it’s surprising to find 200 ancient and giant rocks—the best natural playground in the state! Nowhere else in the world are this many enormous sandstone concretions concentrated in one location. Designated a National Natural Landmark in 1976, the rocks are accessible year round. Small admission charge. Memorial Day-Labor Day, daily 9 a.m.-5 p.m. (8 Wonders of Kansas - Geography)