The White House is most amazing for its open-door policy: It is the only residence of a head of state in the world that's open to the public, free of charge. And while visitors can't tour all 132 rooms, they can see some of the more famous ones, including the East, Blue, Green, and Red rooms. (Public tours of the White House are available for groups of ten or more; however, requests must be submitted through your member of Congress six months in advance.)
In 1790, President George Washington laid out his vision for Washington, D.C., to be situated on a plot of land "not exceeding ten miles square...on the river Potomac." Washington then worked with city planner Pierre L'Enfant to select the spot for the presidential residence --1600 Pennsylvania Avenue.
James Hoban's understated, classical blueprint for the building was selected from a field of nine, and ground was broken in 1792. Eight years later, John and Abigail Adams became the first residents of the White House -- although it wasn't called that until President Theodore Roosevelt gave it that name in 1901. The Adamses made minor changes to the place, as has every president since.
In 1949 while Truman was in office, the White House underwent its only major renovation. The original halls, third floor, and roof were retained, but the rest of the interior was stripped and rebuilt on a new concrete foundation. Since then, several presidents have decorated the interior differently, but the architecture has remained intact.
Tours typically convene in President's Park South, the 52-acre park better known as the Ellipse. The Ellipse is home to several monuments and memorials as well as events such as the famed Easter Egg Roll in the spring and the lighting of the National Christmas Tree in December.