Great Falls is a census-designated place (CDP) in Fairfax County, Virginia, United States. CNNMoney ranked Great Falls first in the nation on its list of “top earning towns” in 2011. Great Falls lies in the Piedmont upland on the right bank of the Potomac River. The river forms the northern and eastern border of the CDP, and several of its tributaries flow north and east through the CDP. From north to south, these include Nichols Run, Clarks Branch, and Difficult Run. Difficult Run forms the southeastern border of the CDP.
As a suburb of Washington, D.C., Great Falls is a part of both the Washington Metropolitan Area and the larger Baltimore-Washington Metropolitan Area. It is bordered on all sides by other Washington suburbs, including: Darnestown and Travilah, Maryland to the north, Potomac, Maryland to the east, McLean to the southeast, Wolf Trap to the south, Reston and Dranesville to the southwest, Sterling to the west, and Lowes Island to the northwest. Fairfax County Public Schools operates the local public schools.