National Guard Memorial Museum is at One Massachusetts Ave. N.W. at jct. N. Capitol St. N.W. It traces the history of the militia and National Guard from 1636 to the global war on terror, highlighted in the 9/11 Era Gallery exhibit. Rooms are laid out chronologically and contain photos, interactive exhibits and such artifacts as uniforms, insignia and weapons. A 12-minute introductory film is also shown.