Jefferson Pier
Jefferson Pier, Jefferson Stone, or the Jefferson Pier Stone, in Washington, D.C., marks the second prime meridian of the United States even though it was never officially recognized, either by presidential proclamation or by a resolution or act of Congress.
The stone is on the National Mall almost due south of the center of the White House and the midline of 16th Street, NW, about due west of the center of the United States Capitol building, almost due north of the center of the Jefferson Memorial and 391 ft (119 m) WNW of the center of the Washington Monument.
The monument is a 2.25-by-2.25-foot (0.7 m × 0.7 m), 3-foot (0.9 m) tall granitic monolith with crossing longitudinal and latitudinal lines engraved on its upper surface and with a defaced inscription engraved on its west face that states:
Position of Jefferson
Pier erected December 18, 1804.
Recovered and Re-erected
December 2, 1889.
[fifth line chiseled out]
District of Columbia
The chiseled-out fifth line reportedly once incorrectly stated: "BEING THE CENTRE POINT OF THE".
According to a notation on Pierre (Peter) Charles L'Enfant's 1791 "Plan of the city intended for the permanent seat of the government of the United States...", Andrew Ellicott measured a prime meridian (longitude 0°0') through the future site of the U.S. Capitol. (Shortly after L'Enfant prepared this plan, its subject received the name "City of Washington".) Thomas Jefferson, who at the time was serving as the United States Secretary of State, supervised Ellicott's and L'Enfant's activities during the initial planning of the nation's capital city. Jefferson hoped that the United States would become scientifically as well as politically independent from Europe. He therefore desired that the new nation's capital city should contain a new "first meridian".
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