Just 15 miles south of Minneola, US Highway 283 bisects the Big Basin, a natural sinkhole thought to have been created by dissolving salts a few thousand years ago, causing the surface to drop 100 feet. The highway traverses 1.04 miles through the basin before climbing to the rim with its nearly vertical walls. The entrance to the Big Basin Prairie Preserve lies at the bottom of the basin, which is now home to about 50 head of free-roaming buffalo. On the drive through the area visitors are cautioned to take care when exiting their cars near the buffalo since these animals can be unpredictable. In the 1800s this area was often an encampment for settlers, cowboys or Indians.