“America’s most historic prison.” Formerly a prison, now open to the public as an architectural landmark, history museum, and art installation venue. Seems very cool.

Tel.: 215-236-3300
Website: EasternState.org
Hours: 10am-5pm, Wed. thru Sun. (last entry 4 pm)
Fees: $9 adults, $4 children age 7-12, no children under 7 allowed.