It is one of the oldest churches in Poland and the oldest Polish cathedral, as it was originally built in the second half of the 10th century. In the 14th and 15th centuries, the church was rebuilt in the Gothic style. At that time, a crown of chapels was added. A fire in 1622 did such serious damage that the cathedral needed a complete renovation, which was carried out in the Baroque style. Another major fire broke out in 1772 and the church was rebuilt in the Neo-Classical style. In 1821, Pope Pius VII raised the cathedral to the status of a Metropolitan Archcathedral and added the second patron - Saint Paul. The last of the great fires occurred on 15 February 1945, during the liberation of the city from the Germans. The damage was serious enough that the conservators decided to return to the Gothic style, using as a base medieval relics revealed by the fire. The cathedral was reopened on 29 June 1956. (Text based on Wikipedia).