One of the oldest U.S. colleges, St. John's started in 1696 as a prep school but was chartered as a college in 1784. Self-guided tour brochures are available in Room 124, Mellon Hall. Mellon is also home to the Mitchell Art Gallery and -- for a completely different style of architecture -- was designed by a student of Frank Lloyd Wright. Two buildings are named for Maryland's signers of the Declaration of Independence, the Chase-Stone House and the Paca-Carroll House, both built in 1857. Don't miss the Carroll Barrister House, built about 1724 for Charles Carroll the barrister, a member of the prominent Maryland family.