section_path: Geography
section_name: Geography
paragraph_text: Geography
  
  Washington, D.C., is located in the Mid-Atlantic region of the U.S. East Coast. The city has a total area of 68.34 square miles (177 km 2), of which 61.05 square miles (158.1 km 2) is land and 7.29 square miles (18.9 km 2) (10.67%) is water. The district is bordered by Montgomery County, Maryland, to the northwest; Prince George's County, Maryland, to the east; Arlington County, Virginia, to the west; and Alexandria, Virginia, to the south.
  
  The south bank of the Potomac River forms the district's border with Virginia and has two major tributaries, the Anacostia River and Rock Creek. Tiber Creek, a natural watercourse that once passed through the National Mall, was fully enclosed underground during the 1870s. The creek also formed a portion of the now-filled Washington City Canal, which allowed passage through the city to the Anacostia River from 1815 until the 1850s. The Chesapeake and Ohio Canal starts in Georgetown and was used during the 19th century to bypass the Little Falls of the Potomac River, located at the northwest edge of the city at the Atlantic Seaboard fall line.
  
  The highest natural elevation in the district is 409 feet (125 m) above sea level at Fort Reno Park in upper northwest Washington, D.C. The lowest point is sea level at the Potomac River. The geographic center of Washington is near the intersection of 4th and L streets NW.