Jefferson Pier, Jefferson Stone, or the Jefferson Pier Stone, (pronounced pie-er, like radials of a pie)[citation needed] in Washington, D.C., marks the second prime meridian of the United States[1] even though it was never officially recognized, either by presidential proclamation or by a resolution or act of Congress.
- ^ David R. Doyle, National Geodetic Survey. "Where Freedom Stands". Retrieved April 20, 2006.