Jefferson Pier

The Jefferson Pier is a granite block roughly three feet tall that stands on an open lawn west of the Washington Monument on the National Mall. Its surface bears engraved lines of longitude and latitude that indicate its former function as a survey marker.

Thomas Jefferson ordered the stone placed in 1804 to create an independent prime meridian for the new United States. Later, surveyors used the marker as one of the starting points for mapping the District of Columbia before it lost its practical importance.

This stone was part of an early effort to base the young republic's surveying on its own foundations rather than relying on European reference points. The idea behind it was that the United States should establish its own scientific coordinates, much as it had become politically independent.

You can find the stone on the lawn between the White House and the Washington Monument by following the straight north-south line through the greenspace. The marker is small and easy to overlook, especially when distracted by the larger obelisk.

The inscription on the stone originally referred to its role as marking the center point of the District of Columbia, but parts of that engraving were later removed. Today the stone stands several feet from its planned original position, as the ground has been reshaped over time.

Location: District of Columbia

Website: https://ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=UA0024

GPS coordinates: 38.88980,-77.03655

Latest update: December 5, 2025 22:30