The fortification consisted of Confederate defensive line about a mile and 3/4 long stretching from the Mississippi River northward to Metairie Ridge. (The area further north from the ridge to Lake Pontchartrain was at the time swamp.) This was intended to protect the city of New Orleans from Union attack from upriver. As the Union fleet took the city by sailing in from below, the fortification was never used. After the capture of New Orleans, U.S. forces manned and expanded the fortifications to defend against a Confederate counter-attack which never came.
The only remaining structure of the fortification is the powder magazine, of brick enclosed in an earth mound. It is located off Causeway Boulevard near the American Legion Post 267, preserved in a small park and added to the National Register of Historic Places in 1977.