Loreta is one of the main pilgrimage sites in Prague. The name goes back to the Italian town Loretto. The legend says that after the Saracens' invasion to Palestine, angels took the Holy House (Santa Casa) first to Dalmatia and then to Loretto. It was the very same house where the Virgin Mary lived and where archangel Gabriel came to her and announced that she would be the mother of God.

Prague Loreta exists thanks to countess Katerina Benigna of Lobkowicz. She ordered to build a copy of the Holy House in 1626 and invited Giovani Batisto Orsi, the architect from Vienna. It is believed that the Holy House in Prague is the most accurate of all copies of the Italian original. The difference is that Italian Santa Casa is located inside of the basilica and Prague is in the middle of the courtyard surrounded by baroque buildings.

The Holy House is a building of square shape. The facades are decorated with stucco depicting scenes from the life of the Virgin Mary. Inside is a statue of the Virgin Mary of Loreto from the 17th century carved out from linden wood.

The House is surrounded by a gallery with six chapels. The Loreta complex also includes the Church of the Nativity of Lord, a tower with a carillon and a treasury.

There are more than 300 precious items in the Loreta treasury. They are mostly monstrances, chalices, little altars. Perhaps the most famous item here is the diamond monstrance named Prague Sun. Countess Lyudmila of Kolowrat received 6500 diamonds as a wedding present from her fiance, who, by the way, was 35 years younger than her. In her will, the countess ordered to give those diamonds to Loreta after her death. Craftsmen in Vienna made a precious monstrance decorated with 6222 diamonds. The rest was used as payment for work. The Prague Sun is made from gold-plated silver and weighs 12 kg.

The main facade of Loreta is the work of architects Kristof and Kilian Ignaz Dietzenhofer. They also created a clock tower with the famous carillon - a musical instrument made from bells. These bells are immovable and are sounded via hammers. Hammers, in turn, are set in motion either by pressing keys on the keyboard or by a clock mechanism. There are 30 bells in Loreta carillon, though only 27 are played (the 3 smallest are not connected to the mechanism). Every hour the hymn “Thousands of greetings to you” is played.