Devil's Millhopper Geological State Park is a National Natural Landmark that has been visited by the curious since the early 1880s. Researchers have learned a great deal about Florida's natural history by studying fossil shark teeth, marine shells and the fossilized remains of extinct land animals found in the sink.
The sinkhole is 120 feet deep and 500 feet across. A one-half mile nature trail follows the rim, and there is a 232-step stairway to the bottom of the sink.
The state purchased this site in 1974, and the stairs were completed in 1976. Until that time, access in the area was limited.