For being some of the only climbing in Kansas, Rock City is pretty cool! The small park is a 5-acre National Natural Landmark and is open from sunrise to sunset. The $3 entrance fee can be paid either at the gift shop (if it's staffed) or slipped in the iron ranger.
The 200 or so giant Dakota sandstone orbs make this place the largest concentration of calcite-cemented concretions in the world. While many are too small or too buried to offer any real climbing, the rock quality is great and there are a number of established classics. After trying the known problems, make up your own by playing "take-away" on the more featured spheres!
There is no approach whatsoever, and the landings are flat dirt or grass. Several trees provide mid-day shade. The park has restrooms, trash cans, benches, and covered picnic tables.