Prague Castle is a castle complex in Prague, Czech Republic, built in the 9th century. It is the official office of the President of the Czech Republic. The castle was a seat of power for kings of Bohemia, Holy Roman emperors, and presidents of Czechoslovakia. The Bohemian Crown Jewels are kept within a hidden room inside it.

Prague Castle is a historical building complex, founded in 880 as a seat of power for the Bohemian Kings. It is a significant monument in Czech history and is considered to be an ancient and important cultural institution of the Czech State.

Prague Castle is located in the heart of the historic center of Prague, which is a UNESCO World Heritage Site. The 110 acres large Prague castle complex is also called Hradčany, a collective name for all the palaces, offices, buildings, churches, and gardens that comes under it. Built on the banks of river Vltava, Charles Bridge connects the ancient castle to the city’s Old Town and other neighboring areas.

Prague Castle is the largest ancient castle in the world, occupying an area of almost 70,000 square meters, at about 570 meters in length and an average of about 130 meters wide. The castle is among the most visited tourist attractions in Prague attracting over 1.8 million visitors annually.

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 the Virgin Mary. Other churches, dedicated to St. George and St. Vitus, were founded in the first half of the 10th century.

From the 10th 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 the church, the Prague bishop. The first convent in Bohemia was also founded on the grounds of Prague Castle, a convent next to the church of St. George for the order of Benedictine nuns.

The castle buildings represent many of the architectural styles of the last millennium. Prague Castle includes Gothic St. Vitus Cathedral, Romanesque Basilica of St. George, a monastery, and several palaces, gardens, and defense towers. Most of the castle areas are open to tourists. The castle houses several museums, including the National Gallery collection of Bohemian baroque and mannerism art, the exhibition dedicated to Czech history, the Toy Museum, and the picture gallery of Prague Castle, based on the collection of Rudolph II. The Summer Shakespeare Festival regularly takes place in the courtyard of Burgrave Palace.

Considered the largest coherent castle complex, Prague Castle includes various historic buildings, palaces, offices, gardens, courtyards, and churches, of various architectural styles, attracting visitors and art lovers from all over the world.

According to Wikipedia