The American Meridian Line (looking south)

This line is built into the red brick sidewalk on the southeast corner of H and 24th Streets NW on the western edge of the campus of George Washington University in the Foggy Bottom neighborhood of Washington, DC. It is on the Washington Meridian through the small dome of the Old Naval Observatory about four blocks due south, southwest of the corner of E and 23rd Streets. This meridian was officially established by an act of Congress on September 28, 1850.