After the end of Ottoman rule, Bishop György Fenessy no longer wanted to live in the castle, so he purchased two construction sites in the city, and the tuff stones that were necessary to build the palace were extracted from the hill behind it, so the Bishop's Palace was built and a huge vault system was established under the town The empty space left by the extraction of rocks. This vault has a relatively cold climate and is excellent for storing local goods. It extends for 3 kilometers under the town from the Hatvani Gate to the Rak Gate. The most beautiful part of the current vault is the colonnaded hall, whose system resembles a chessboard.