Harbour Square

Historical marker location:

1325 4th Street Southwest, Southwest Waterfront, District of Columbia

( Marker is at the intersection of 4th Street Southwest and O Street Southwest, on the right when traveling south on 4th Street Southwest.)

The city was built on a swamp: The area that is now Washington, D.C. was originally a swampy, marshy region along the Potomac River. The construction of the city involved extensive drainage and landfill projects to make the land suitable for building.