Keywords: CapitolGatehouse.jpg Capitol gatehouse in Washington DC USA; Composed of Aquia Creek sandstone http //pubs usgs gov/gip/stones/stones3 html 2009-05-11 USG USG PD-USGov Check categories 2009 June 12 en wikipedia Aquia_Creek_sandstone Sandstone Geology 5 Stafford County Virginia Sandstone buildings in the United States |