Here is an engineer's drawing, showing the layout of Fort Totten and a battery 1,000 yards to the north.

This photograph from the Library of Congress shows several cannon in their firing positions along one wall, looking toward the south.  The building visible in the rear may be a cook house.  These photos was taken in 1864, when the fort was manned by the 3rd Massachusetts Heavy Artillery.

Here is the largest gun at Fort Totten, a 100 pound Parrot rifle.  This was a large-caliber, long-range rifled cannon, one of the largest types used in the war.  Note especially the clear field of view, and the rolling hills and farmland in the distance.  This photo was taken facing north, toward Silver Spring, Maryland.  Today, the site of the fort is overgrown with forest, and the surrounding area is a fully-developed region of suburban Washington.

This photo shows the main entrance to the fort, called the "sally port."

Here is a group of artillery sergeants in front of one of the guns.  This view may also be facing south; it is hard to be sure what is in the background.

This photo shows a group of officers in front of their quarters at Fort Totten.

Fort Totten today has been described as "well preserved."  Take a look.