The Plaza Puerta del Sol is a bustling, centrally located square, which site used to be the eastern border of the city.  The semi oval square was created in the 19th century. In the middle of the square is a large equestrian statue of King Carlos III. On one site of the square is the former main post office, a 18th century red brick building. The Puerta del Sol is also the location of the symbol of Madrid: a 20 ton statue of a bear eating fruits from a tree.