THE IMAGE OF THE ALTAR OF ST. PETER'S BASILICA IN THE ROMAN CHURCHES OF THE 12-13<sup>TH</sup> CENT
The Main purpose of the study is an analysis of influence of the image of St. Peter's Basilica on the Roman church architecture of the 12th-13th centuries. It is possible to search the special type of the presbytery, characterized by uniting of the altar on the pedestal and the reliquary “confession” in the general vertical composition. The congregation of these churches had opportunities to see the process of worship and approach the saint relicts. The altar stood so that the Priest served the mass facing the worshippers, as it was in San Pietro. So, this important monument of Rome could be a model for the other churches of the Middle Ages. Among the churches of this period, such features have the altar space of San Giovanni in Laterano, as well as the basilicas of San Giorgio in Velabro, Santa Maria Assunta in Anagni and Santi Giovanni e Paolo in Ferentino. All these buildings was connected with the Power of Papa.