Prague Castle is an architectural complex located in Prague, the capital of the Czech Republic. Despite the successive fires and invasions, it is one of the most remarkable, sumptuous, and emblematic vestiges of the city's great historical, cultural and social past.

The castle is located on Hradčany hill and dominating the Old Town of Prague and Lesser Town. The Prague Castle emerges from a crown of gardens and roofs and deploys its long horizontal facade from which the towers of St. Vitus Cathedral and St. George's Basilica. It is considered to be the largest ancient castle in the world, with a footprint of 570 meters long and 130 meters wide.

Built in the 9th century, it was the residence of the kings of Bohemia, Holy Roman Emperors, Presidents of Czechoslovakia, Reinhard Heydrich during his position as protector of the Protectorate of Bohemia and Moravia in the German occupation of World War II and Presidents of the Czech Republic. In the fortified structure are the Crown Jewels of Bohemia.

The interior of the complex houses the Prague Cathedral, the St. George's Convent containing ancient Bohemian art, St. George's Basilica, the Royal Palace, Renaissance and Baroque painting galleries in the old castle stables, among many other things.

It was remodeled by the architect Jože Plečnik between 1920 and 1934 at the request of the first Czechoslovak president Tomáš Masaryk.