At its opening in 1907, the main hall of Union Station was the largest room under a single roof in the U.S. -- 22,000 square feet larger than its nearest rival, New York's Grand Central Station. Today it is still an active train depot and one of the most beautiful shopping malls you'll ever see.

U.S. Capitol Eastern Market U.S. Marine Barracks U.S. Supreme Court Library of Congress

Lincoln Park Home of John Philip-Sousa Folger Shakespeare Library Sewall-Belmont House