The two-storey building is considered to be one of the most beautiful monumental buildings in Győr. It got its present shape in the 18th century. On the keystone of the central arched stone frame, the initials of the former resident and contractor, subaltern Mátyás Sajnovics, and the year of the construction of the building – 1703 – can be seen. The wall facade of the building is divided by wall pillars.

Its main decoration is the beautiful baroque shuttered window under which the relief representation of St. Rosalia of Palermo can be seen, who is the patron saint of patients suffering from the plague. This is where the name of the building stems from.