It is the foundation of the Russian school of architecture that the lecture concentrates on. The first stone buildings whose beauty and perfection did not fade over almost ten centuries are described. Using the history of the Church of the Transfiguration of Our Savoir on Nereditsa Hill as an example, the development of architectural archaeology is studied. This science allows us to reconstruct the original look of the building, as well as to study the archaeological material, organise and manage the process of the reconstruction of a building.