The Pentagon

[[File:The Pentagon US Department of Defense building.jpg | thumb | The Pentagon is right across the Potomac River from Washington, D.C. The Pentagon is a very large office building that houses the headquarters for the US Department of Defense. The building was built with five concentric rings. The building has five sides - hence the name.

Colloquially, the Department's senior leadership, who meet in the Pentagon, are referred to as "The Pentagon", when discussing decisions made there.