 Complete the following phrase:  The Gniezno Doors ,  are a pair of bronze doors placed at the entrance to Gniezno Cathedral in Gniezno, Poland. They are decorated with eighteen bas-relief scenes from the life of St. Adalbert in Polish, Wojciech, whose remains had been purchased for their weight in gold and brought back to, and enshrined in, the cathedral. The cathedral is a Gothic building which the doors predate, having been carried over from an earlier temple. The doors were made about 1175, in the reign of Mieszko III the Old, and are one of the most important works of 