Park daily 4 a.m.-10:30 p.m. Visitor center open Sat.-Sun. and holidays 9-5, early May-early Oct. Interpretive program Fri. beginning at 6 p.m. to 8:30 p.m., May-Aug. Outdoor movie Sat. at 8:30 p.m., May-Aug.; phone ahead. Caves are closed Oct. 15-Apr. 15 for bat hibernation period. Phone ahead to confirm entry to the caves and guided tour and program schedule.