Loreta is a complex of buildings located at the east side of the Loretan Square, opposite of the Czernin Palace. The name of the religious complex is given after the Italian pilgrimage site, Loreto, near Ancona. The legend says that angels and pilgrims moved the whole Holy House of Nazareth (Casa santa), where angels appeared to the Virgin Mary and told her about arrival and the birth of Jesus. Similar to other places in the world, the Casa Santa was rebuilt in Prague and it became an important pilgrimage spot that was only comparable with the Church of the Virgin Mary Victorious, where there is the statue of the Infant Jesus of Prague.
For the construction of the Loretto Chapel it was promoted by the Capuchins, who were from the nearby monastery and its patron, Kateřina Benigna von Lobkowicz. In 1626, she ordered the chapel from the architect, Giovanni Orsini. For the construction, he supposedly used several pieces of bricks and beams from the Italian Loreto. The Holy House was enclosed with Baroque cloisters at the beginning of the 18th century. The main façade was started by Christoph Dientzenhofer but finished by his son, Kilian Ignaz. In the central part of the façade, there is a bell tower with a well-known and rare carillon consisting of thirty synchronized bells. Another part of the Prague Loreta is the Loretan Treasury. It mostly consists of Baroque goldsmith relics, chalices, monstrance and reliquaries. The biggest attraction is called the Prague Sun monstrance, and it was made in Vienna and designed by Johann Bernhard Fischer von Erlach. The monstrance is decorated with 6,222 diamonds.