Seaford Hundred in Sussex County, Delaware — The American Northeast (Mid-Atlantic)
Oak Grove Crownstone
Photographed by Beverly Pfingsten, November 12, 2010
1. Oak Grove Crownstone Marker
Inscription.
Charged with marking the long-disputed boundaries of the colonies of Maryland and Pennsylvania (including the Three Lower Counties of Delaware), English astronomers Charles Mason and Jeremiah Dixon landed in America on November 15, 1763. The following June they traveled to a place on the Delmarva Peninsula which had been previously determined to be mid-way between the Atlantic Ocean and the Chesapeake Bay. Known as the Middle Point, it is now the southwest corner of the State of Delaware. From there they journeyed northward, proceeding with the painstaking task of surveying a line to intersect with a location 12 miles distant from the Town of New Castle. Temporary wooden markers were placed at one-mile intervals. On July 6, 1764, they arrived here, fifteen miles north of their place of beginning. In December 1765 they returned to this area to replace the temporary markers with stones imported from England. At intermediate mile points the stones were marked with the letters P and M on reverse sides. At every five-mile point the stones were engraved with the coats of arms of the Calvert and Penn families, proprietors of
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the colonies. Mason and Dixon completed their work in January 1768. The boundaries were formally approved in 1775.
Erected 2003 by Delaware Public Archives. (Marker Number SC-178.)
Topics and series. This historical marker is listed in this topic list: Colonial Era. In addition, it is included in the Delaware Public Archives series list. A significant historical month for this entry is January 1768.
Location. 38° 40.653′ N, 75° 42.646′ W. Marker is in Seaford, Delaware, in Sussex County. It is in Seaford Hundred. It is on N. Oak Grove Road close to Kinder Road, on the left when traveling north. Touch for map. Marker is in this post office area: Seaford DE 19973, United States of America. Touch for directions.
Regionally, this marker is in the American Mid-Atlantic, on the Delmarva Peninsula, and on the Eastern Seaboard. Globally, it is in the North Atlantic Region, North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once New Netherland, one of the original Thirteen Colonies, and the Antebellum South.
Other nearby markers. At least 8 other markers are within
Photographed by Beverly Pfingsten, November 12, 2010
3. Oak Grove Crownstone
Maryland side.
Photographed by Beverly Pfingsten, November 12, 2010
4. Oak Grove Crownstone Marker and stone
Credits. This page was last revised on June 29, 2026. It was originally submitted on December 2, 2010, by Bill Pfingsten of Bel Air, Maryland. This page has been viewed 1,145 times since then and 27 times this year. Photos:1, 2, 3, 4. submitted on December 2, 2010, by Bill Pfingsten of Bel Air, Maryland.
