Zero Milestone

The Zero Milestone is a zero mile marker monument in Washington, D.C. intended as the initial milestone from which all road distances in the United States should be reckoned when it was built. At present, only roads in the Washington, D.C. area have distances measured from it.

The monument stands just south of the White House at the north edge of the Ellipse, within President's Park. Atop the monument is a bronze 16-point compass rose with a very small worn-down pyramid at its center whose top serves as a National Geodetic Survey benchmark (HV1847).

Designed by Washington architect Horace W. Peaslee, the monolith is about 2 feet square and about 4 feet high. It is made of precambrian Milford granite from Milford, Massachusetts, light pinkish to greenish gray, with spots of black biotite mica. The bronze disk on top of the milestone is "an adaptation from ancient portolan charts of the so-called wind roses or compass roses from the points of which extended radial lines to all parts of the then known world—the prototype of the modern mariner's compass."

The monument has engravings on four surfaces:

In addition, a "brass plate placed on the ground at the north base" shown below, contains the following inscription.

In his plan for Washington, Pierre Charles L'Enfant intended a column to be placed 1 mile east of the Capitol, of which is now Lincoln Park, "from which all distances of places through the continent were to be calculated." Instead, in 1804, the Jefferson Stone or Jefferson Pier was placed on the meridian of the White House due west of the Capitol (119 m WNW of the center of the Washington Monument) to mark the Washington meridian, 77° 02' 12.0".

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