$6; $5 (ages 4-18 and 62+); $20 (family, two adults and up to four children ages 4-18); donations (Wed. 5-7, July-Aug.); free (active military with ID).
Daily 11-5 (also Wed. 5-7, July-Aug.), Memorial Day-Labor Day; Tues.-Fri. noon-4, Sat.-Sun. 11-5, rest of year. Closed major holidays. Phone ahead to confirm schedule.