A magnificent cathedral, the Cathedral of the Assumption of the Blessed Virgin Mary, is a true adornment of Helsinki. It was designed by the outstanding Russian architect Alexey Mikhailovich Gornostayev at the request of Governor-General Fyodor Fyodorovich Berg. The idea to build a large cathedral arose in 1854 thanks to the 24-year-old rector of the Holy Trinity Church, Father Nikolai (Popov), who informed the governor-general that his church could not accommodate all the parishioners and suggested building a new cathedral for the large city. Fyodor Fyodorovich immediately took note of this and began searching for a suitable architect. The first project was proposed by Professor Stepan Ivanovich Baranovsky from the University of Helsingfors, but the baron rejected it and turned to the capital architect Alexey Mikhailovich Gornostayev. This architect, a student of Zhilyardi and a renowned master, was initially reluctant to participate in the project; however, the governor-general managed to negotiate with him. The project was personally approved by Emperor Alexander II.

Construction began in 1862, and by 1868 the cathedral was completed and solemnly consecrated in honor of the Assumption of the Blessed Virgin Mary. Unfortunately, Alexey Mikhailovich Gornostayev did not live to see the completion of the construction, passing away shortly after the foundation was laid. The construction was continued under the leadership of Academician Ivan Alexeyevich Varnek. Despite all the difficulties, the cathedral turned out magnificent, executed in the neo-Russian style, reminiscent of the early church architecture of ancient Rus. Fortunately, revolutionary upheavals bypassed this remarkable temple. Unlike the Bolsheviks, the Finns treated churches with respect, and it has survived to this day.