1 The Pentagon, the renowned US Department of Defense facility in Washington, D.C. 2: Home plate on a baseball field School crossing guards A soccer ball is divided into four pieces. One piece is marked with the number 1; another with the number 2; and so on, up to number 8. The goal is for each player to be given one piece of the soccer ball. 3 The Pentagon has nine buildings across an area of about 44 acres (17 ha). They include the H-hour Clock Tower, the Pentagon Memorial, and the Pentagon Vista. 4 The Pentagon was built between 1941 and 1945 under the direction of George M. Steinman by the Army Corps of Engineers. It is estimated to be the largest office building in world history at this time. The total cost was $US125 million ($1.9 billion in 2015 dollars). 5 The Pentagon was designed to be self-sufficient with its own power supply, water treatment facilities, and food storage areas. It also has its own fire department and police force. 6 The Pentagon has two main entrances: one on 17th Street (for visitors) and another on Massachusetts Avenue (for employees). There is a third entrance located at the Veterans Affairs Medical Center next door but it is only open to patients and staff members.