A castle was established on this site in the 9th century, and a Romanesque palace was erected in the 12th. In the 14th century, under the reign of Charles IV, it was rebuilt in the Gothic style. The final reconstruction of the Royal palace took place under the Jagellons at the end of the 15th century, and at that time the builder Benedikt Rejt added the now-famous Vladislav Hall, also in Gothic style. The castle was enlarged in the 16th century, especially after a big fire in 1541. The Spanish Hall, in a new part of the castle, was added in the reign of Rudolf II, and it took its final form in the time of Empress Maria Theresa, under the direction of the architect M. Pacassi. After World War I the interior and gardens of the castle were renovated by the architect J. Plecnik. Today the Castle is the seat of the President of the Czech Republic, and it serves as the historical and political center of both city and state. The changing of the guard takes place every hour on the hour, from 5 a.m. to 11 p.m. Each day at noon there is also a solemn fanfare.