The area was developed during the 1970s by the 7th Infantry division and utilized as an advanced training area. The training area included a small town (called Dodge City) that had pop up shooting targets of bad guys and good guys. In the late 1980s the Impossible City was built to train the infantry in urban assault tactics. Impossible City derives its name from the way the city is built, all areas can be easily seen from adjacent buildings, and most doors open to a central area. Today the facility is run and used by the FBI for urban training. The FBI subleases the area to local law enforcement agencies and military units such as the Navy Seals. This area is off limits to the general public.