[2] Acts of Assembly, 1920, Chapter 241. The present boundaries of Arlington may be described as: Beginning at the intersection of Four Mile Run with the west shore line of the Potomac River, westwardly, in general along the line of Four Mile Run, without regard to its meanders, intersecting the south right-of-way line of the Washington and Old Dominion Railroad, then 1,858.44 feet to where the center line of Shirlington Road intersects the said south right-of-way line; thence south and slightly east to the center line of Quaker Lane, then following the center line of Quaker Lane to a point short of Osage Street in Alexandria where it moves to the north line of Quaker Lane; thence to the east right-of-way line of Leesburg Pike (King Street); thence with this line to the east side of 30th Street, South, in Arlington, northeast on 30th Street, South, to the circle; around said circle to the north side of South Columbus Street, along this line to 28th Street, South, returning for a short distance to Leesburg Pike, jogging east and north to 25th Street, South, and then back to Leesburg Pike; thence along the Pike to the common boundary of Alexandria and Fairfax; thence northeast along the former Alexandria-Fairfax boundary until it intersects the original boundary between Arlington and Fairfax; thence due northwest to a stone and large oak tree approximately 200 feet west of Meridian Avenue (North Arizona Street); thence due northeast to the shore of the Potomac; thence along the mean high water mark of the shore of the Potomac River, back to the point of beginning. This line encloses roughly 16,520 acres, or approximately 25.7 square miles, thus making Arlington the third smallest county in the United States in respect to area.[3] [3] The smallest is Kalawao County, Hawaii, and the second smallest, Bristol County, Rhode Island. The boundaries of this area have been changed many times since it was first sighted by Captain John Smith on his voyage up the Potomac in 1608--the year which can be said to mark the beginning of Arlington's history. _1608-1789_