Washington and Alexandria Road, and extending to the intersection of the said Run with the Potomac River; thence following along the west shore line of said Potomac River southwardly to the point of beginning." _Boundary Adjustment 1966_ Text of the description of the new Arlington-Alexandria boundary in effect on January 1, 1966, by mutual agreement: "A line beginning at a point on the common boundary between Fairfax County and the City of Alexandria, Virginia, said point being in the existing right of way of Route #7 and is further defined as point #134 having Virginia State Coordinates of N. 431,495.42 and E. 2,395,581.64 as shown on a map recorded with a deed of annexation in Deed Book 332, page 559, of the land records of the City of Alexandria, Virginia; thence running along said common boundary N. 55 deg. 50' 10" E., 69.09 feet to the boundary corner #135 whose coordinates are N. 431,534.22 and E. 2,395,638.81, said point #135 also being shown on the aforementioned boundary map; thence still running with the last mentioned course and across Route #7 1.29 feet (70.38 feet in all) to a point having coordinates N. 431,534.94 and E. 2,395,639.88; thence running N. 09 deg. 13' 10" E. 0.69 feet to a point lying on the northerly side of Route #7, 40 feet from same and having coordinates N. 431,535.62 and E. 2,395,639.99; thence running along the northerly side of Route #7 S. 66 deg. 38' 20" E., 96.13 feet to a point of curvature whose coordinates are N. 431,497.50 and E. 2,395,728.24 thence continuing with said northerly side of Route #7 and its extension and following the arc of a curve to the right whose radius is 2331.83 feet and whose chord and chord bearing are 810.17 feet and S. 56 deg. 38' 05" E. respectively, for an arc distance of 814.30 feet to a point on the extension of the northerly side of 25th Street, and whose coordinates are N. 431,051.93 and E. 2,396,404.88; thence running along said extension and thence with the northerly side of said street N. 50 deg. 54' 13" E., 39.53 feet to a point of curvature whose coordinates are N. 431,076.86 and E. 2,396,435.56; thence following the arc of a curve to the right whose radius is 115.60 feet and whose chord and chord bearing are 42.17 feet and N. 61 deg. 24' 48" E. respectively, for an arc distance of 42.41 feet to a point of tangency whose coordinates are N. 431,097.04 and E. 2,396,472.59; thence continuing along 25th Street N. 71 deg. 55' 23" E. 220.00 feet to a point whose coordinates are N. 431,165.30 and E. 2,396,681.73; thence turning and running across 25th Street and thence along the common boundary between lots #503 and #5 of Section 1 of Claremont Subdivision, and thence across Beauregard Street (its extension into Arlington County being known as S. Walter Reed Drive) S. 18 deg.