THREE PHOTOS TO LEFT: These photos, taken in 2000, show advancing views of the of the area by the Fort Myer South Post/Pentagon tunnel, which soldiers in Headquarters Company walked through for their duty in the Pentagon. The tunnel was underneath Washington Boulevard, ending at a cement staircase which was near the Mall Entrance. The photographer is standing at the former location of the South Post pool.

BELOW PHOTOS: The shot on the left is also from 2000 and the other view, from early 2008 shows the entrance much more overgrown with brush. Note also the newly-built wall between Washington Boulevard and The Pentagon, which is the border for a 9/11 tribute area. Today, this tunnel entrance is the only remnant left of South Post. Photos by Bill Jentz