The hotel is located in a historic XIX century mansion, which is protected by the state as an object of architectural heritage. The elegant facade of the building is decorated with Atlantean figures. Helvetia consists of two buildings, the first of which overlooks Marata Street, and the second is hidden at the heart of a romantic courtyard.
The mansion received its current neo-Baroque architectural appearance back in 1850. The building was designed by the architect August Lange, and one of the suites of the hotel is named after him. Originally, Marata Street was called Preobrazhenskaya, and then Nikolaevskaya. The street received its current name in 1918, when the city authorities decided to name it in honor of the French revolutionary Jean-Paul Marat.