Satellite image of Washington DC, USA. Near center, there is a straight green line which is the National Mall, with the Capitol Building at its eastern end and the Lincoln Memorial at its west. The White House sits just north of the Mall. About 20 percent of the Districts area is covered by parkland, including Rock Creek Park which appears as a dark green area at the upper center. This parkland follows the flow of Rock Creek, a tributary to the larger Potomac River. Farther southeast, the Anacostia River also flows into the Potomac. The large green area at the upper right is part of the Patuxent Research Refuge in Maryland, a wildlife refuge spanning over 50 square kilometres dedicated to protecting wildlife and habitat. The NASA Goddard Space Flight Center is located nearby. Data obtained by the Copernicus Sentinel-2A satellite on 25 August 2015.