Andrew Ellicott
Andrew Ellicott (1754-1820) was one of the great American surveyors and mapmakers of the late 18th century. After serving in the Revolution, in 1784 he worked with David Rittenhouse and Bishop James Madison to complete the survey of the Mason-Dixon Line between Maryland and Pennsylvania. These connections proved valuable, and in the following years he conducted important surveys for the State of Pennsylvania, including its western boundary with the Ohio Country.
Ellicott’s connections and reputation was such that in January 1791 President Washington engaged him to conduct a topographical survey of the area of the District of Columbia, while Pierre L’Enfant was hired to develop a plan for the new capital city of Washington. L’Enfant was brilliant but difficult, so much so that President Washington eventually fired him in 1792 and engaged Ellicott, who used L’Enfant’s design as the basis for his plan of the city.
In 1796 Washington engaged Ellicott once again, this time for the joint survey of the boundary between Spanish West Florida and the United States, as established by the Treat of San Lorenzo. In 1803 he helped train Merriwether Lewis in advance of the latter’s transcontinental exploration. In 1813 he was appointed to teach at West Point, where he lived until his death in 1820.
Andrew Ellicott (1754-1820) was one of the great American surveyors and mapmakers of the late 18th century. After serving in the Revolution, in 1784 he worked with David Rittenhouse and Bishop James Madison to complete the survey of the Mason-Dixon Line between Maryland and Pennsylvania. These connections proved valuable, and in the following years he conducted important surveys for the State of Pennsylvania, including its western boundary with the Ohio Country.
Ellicott’s connections and reputation was such that in January 1791 President Washington engaged him to conduct a topographical survey of the area of the District of Columbia, while Pierre L’Enfant was hired to develop a plan for the new capital city of Washington. L’Enfant was brilliant but difficult, so much so that President Washington eventually fired him in 1792 and engaged Ellicott, who used L’Enfant’s design as the basis for his plan of the city.
In 1796 Washington engaged Ellicott once again, this time for the joint survey of the boundary between Spanish West Florida and the United States, as established by the Treat of San Lorenzo. In 1803 he helped train Merriwether Lewis in advance of the latter’s transcontinental exploration. In 1813 he was appointed to teach at West Point, where he lived until his death in 1820.
![[Andrew Ellicott] / [James] Thackara & [John] Vallance Sc[ulpsit], PLAN of the City of WASHINGTON. [Philadelphia, March 1792.]](https://bostonraremaps.com/wp-content/uploads/2026/09/BRM5094-Thackara-Vallance-small-Washington-1792_lowres-500x400.jpg)
