Unique written and architectural monuments of Islam. They became the unifying factor that connected the East and the West. An example of the deepest ties of Muslims of Russia and Uzbekistan are the historical facts about the construction of the Cathedral Mosque in St. Petersburg more than a century ago. The northern capital of Russia possesses exclusive collections of written masterpieces created and copied on the territory of Uzbekistan, but by the will of fate ended up on the banks of the Neva. Katta Langar Quran – the rarest copy of the sacred list of Muslims, dating back to the 8th century. Since the 19th century it has been kept in St. Petersburg. This article talks about the construction of a mosque in St. Petersburg and the history of the sacred Muslim manuscript.