DC fire and ems personnel rescued a woman from a steep slope near the east side of the Calvert Street Bridge, authorities said. (DC Fire and EMS photo)

Many consider Washington to be a sort of swamp. And visitors to the Mall see a broad and flat expanse. But the District has steep slopes too, and rugged topography, and the D.C. fire department made a rescue Friday night on such terrain.

An injured woman was part way down the steeply pitched slope in the 1900 block of Calvert Street NW, near the Calvert Street bridge, which runs high above Rock Creek, according to authorities.

She was rescued Friday night with what Fire Department spokesman Vito Maggiolo said were non lifethreatening injuries.

It was not clear how she came to be about 25 feet down the slope, Maggiolo said.

The rescue operation was intricate. White-helmeted firefighters rappelled down to her from street level Maggiolo said. Equipment used included a Stokes basket. A pulley system was set up supported by three metal poles, arranged like a tripod. Floodlights were in use.

Fire department video shows at least four firefighters at ground level.

Then suddenly, the Stokes basket, seems to rise from beyond the lip of the slope, like an elevator coming from a lower floor.

The woman was rescued.