The Twelve Collegia building in St. Petersburg, one of the first constructions in the city, was erected in the "Peter's Baroque" style by order of Peter I to house the colleges, the Senate, and the Synod he established. However, the tsar's plans to move the city center to Vasilievsky Island, which was prone to winds and floods, did not materialize. Nevertheless, the building has served a noble purpose for two centuries, housing St. Petersburg University.

Vasilievsky Island, with its spit dividing the Neva, reminded Peter I of Holland, and he decided to relocate the port and administrative center of the new capital there. State institutions, the Senate, the Synod, and the colleges were to convene here. A building suitable for the new status of Russia was required.

The reforming tsar replaced orders with colleges, such as the "College of Foreign Affairs," the "Military College," and others. Instead of the Boyar Duma, he established the Senate, and the Synod became the main church body of Russia. All colleges were to be placed behind a single facade to save funds and emphasize their joint work for the benefit of Russia. The architect was Domenico Trezzini, inspired by the Exchange in Copenhagen and the order buildings in Moscow.

According to Trezzini's design, the island space was to be divided into quarters with canals and three squares. The Twelve Collegia building stretched 400 meters along Collegial Square, perpendicular to the Neva. A historical anecdote claims that Alexander Menshikov, the first governor of St. Petersburg, changed the building's location, but this is merely a fabrication.

Construction began in 1722 and lasted for 20 years, finishing after Peter's death. The tsar personally participated in the project, making changes. As a result, the first floor was built according to Trezzini's plan, while the second and third floors followed Schwertfeger’s design. By 1727, the building was ready, and the colleges began to move in.

Trezzini, dreaming of his native Italy, built an open gallery for shops, which later became the legendary corridor of the university. The architect did not account for the climate, leading to leaking roofs. After his death, the building was completed by Mikhail Zemtsov and Giuseppe Trezzini, who altered the roofing and added the gallery.

Over 300 years, the building has been repeatedly reconstructed, preserving only the Peter's Hall. In the 1960s, the original ceiling painting was discovered. Now, this hall hosts university ceremonies.

When the building was completed, Empress Elizabeth Petrovna sent the Senate, the Synod, and the Foreign College there. However, officials did not like the conditions on Vasilievsky Island, and in 1763 they moved to the other bank of the Neva. In 1824, a flood inundated the archives in the building's basements, damaging most of the documents.

In the early 19th century, the building was transferred to St. Petersburg University. Apollon Shchedrin completed its exterior by arranging the grand staircase and assembly hall. Many famous personalities, such as Mendeleev, Sechenov, and others, walked through the university corridors.

Dmitry Mendeleev worked and lived at the university, where he discovered the periodic law of chemical elements. After a conflict with the minister, he left the university, and his apartment became a museum.

Until the early 20th century, there was a large square in front of the building until the Institute of Obstetrics and Gynecology was built. Now, the Twelve Collegia building is the oldest part of the State University of St. Petersburg. In 2007, a monument "To the University Students" adorned its entrance, and unusual sculptures are located in the courtyard.

The building has its ghosts: a student searching for books and a headless girl. The embankment by the building is a great place for walks. You can enter for free thanks to the "Open City" project, which will resume in the spring.