Archcathedral Basilica of St. Peter and St. Paul Poznań Tags: Religious Building.The Archcathedral Basilica of St. Peter and St. Paul in Poznań is one of the oldest churches in Poland and the oldest Polish cathedral dating from the 10th century. It stands on the island of Ostrów Tumski north-east of the city centre. thumbnail point latitude 52.4114 longitude 16.9478 Learn more... Loading...