This is the official residence of the President of the United States and seat of the executive branch. It is located at 1600 Pennsylvania Avenue NW and has been the residence of every president since John Adam in 1800. Designed by Irish architecture James Hoban, its construction took place between 1792 and 1800. Due to the crowding within the executive mansion itself, President Theodore Roosevelt relocated all work offices to the newly constructed West Wing in 1901. In 1909, President William Howard expanded the West Wing and created the first Oval Office- the official office room of the US President. The East Wing is used as a reception area for social events.