The Venetian Palace of count Collalto was built in 1671 in Baroque style. Originally, the façade was topped by a triangular pediment, which was then demolished. The Palace balcony was connected with the neighbouring Church of the Nine angelic choirs, was provided the opportunity pass.

Once this was originally a Jewish garden. Ferdinand I bought these lands for 26,000 guilders for the school. In 1560, the school was transferred to the Jesuits, who greatly expanded and renovated.

In the early 17th century the building was in the possession of count Thurzo. Thurzo was a Protestant, and after the defeat in 1620 the choice of Protestants was small: to leave the country or to belong to the Catholic Church, Therefore, in 1620, the Thurzo house was confiscated by the Emperor Ferdinand II and donated to the Italian Duke R. Collalto, who was an ardent Catholic.

In 1671 was the reconstruction of the building had a second floor. After the death of count Collalto, the facade of the Palace was updated.

In the second week of October, 1762, in the Palace of the count had held his first public concert six-year-old Wolfgang Amadeus Mozart in front of an audience of Vienna. The concert turned out sensational, Mozart around whole Europe. On this occasion, in June 1956 on the facade of the Palace was a memorial plaque.

In 2001 was held last major overhaul, the building passed into the possession of Bank Austria.

A few years ago, in the basement of the Palace of Collalto archaeologists found the remains of two houses of the 15th century, and the walls that were even older (probably 13th century). Absolute sensation was the opening round of the room, which was surrounded by a stone wall two metres thick. According to Lady Frederick, curator of the state Management of Federal monuments, strange building was a tower early 13th century. Experts suggest that it is part of the Palace, built by Henry II.