The early medieval castle site was fortified with a moat and a rampart of clay and stones. The first walled building was the Church of Our Lady. Other churches, dedicated to St. George and St. Vitus, were founded in the first half of the 10^th century.
From the 10^th century Prague Castle was not only the seat of the head of state, the princes and later kings, but also of the highest representative of church, the Prague bishop. The first convent in Bohemia was also founded in the grounds of Prague Castle, a convent next to the church of St. George for the order of Benedictine nuns.
The period of the rule of King and later Emperor Charles IV. was a time of prosperity for Prague Castle, for then it first became an imperial residence, the seat of the ruler of the Holy Roman Empire. The royal palace was magnificently rebuilt and the fortifications strengthened. Building began on the Gothic Church of St. Vitus on the model of French cathedrals. Building continued on the Castle during the reign of Charles's son, Wenceslas IV.
The Hussite wars and the following decades, when the Castle was not inhabited, caused the dilapidation of its buildings and fortifications.
Until the 17^th century Prague Castle was the residence and seat of the sovereigns, their court and the highest secular and ecclesiastic authorities. Twice in the course of its history it was the centre of a large Central European formation - the Holy Roman Empire. Later its importance declined for three whole centuries. After the origin of the Czechoslovak Republic in 1918 Prague Castle once again became the centre of the state.
Nowadays it is the seat of the president of the Czech Republic and his office. It is no longer the residence of the head of state, but new roles have appeared for it - Prague Castle is an important state property and an attractive destination for visitors from the whole world. For this reason was established the Prague Castle Administration whose task lies in caring for this exceptional cultural and historical monument, its buildings and precincts and their best use.
Apart from institutions historically connected with Prague Castle, various other scientific and educational institutions and non-profit-making organizations also have their seat at Prague Castle.

The Changing of the Guard takes place every hour on the hour. At noon it includes a fanfare and flag ceremony in the 1^st courtyard.

The grounds of the Castle are open daily from 5 a.m. to 12 p.m. (in winter from 5 a.m. to 11 p.m.)
The interiors of the historic monuments are accessible to view with the ticket of Prague Castle Administration.
The gardens of Prague Castle are open daily from 10 a.m. to 6 p.m. (free entrance). Most of the monuments are accessible to wheelchairs. (St. Vitus Cathedral (the main entrance), Old Royal Palace (Vladislav Hall), St. George Basilica, Prague Castle Gallery, Royal Summer Palace, Ball-game Hall, Imperial Stables, Spanish Hall, Rudolph's Gallery from the Broad Corridor, the Gardens of the Prague Castle, WC near St. Vitus Cathedral.)