A look inside the Pentagon, the heart of the US military

The Pentagon in Arlington, Virginia – the primary headquarters for the Department of Defense – was originally constructed in 1941 after War Department officials complained of too little office space in their old headquarters. Two years and 6.5 million square feet later, the Pentagon was born. Standing seven stories tall and overlooking the nation’s capital,the building houses about 27,000 personnel and three branches of the U.S. military.