Płock has great archival traditions dating back to the 13th century. At that time, the Archive of the Płock Castle was established - one of the oldest archives in Poland. It collected files created by the chancellor and the starost. The staroste supervised the castle, managed the prince's estates and exercised judicial power over the castle. With time, he handed over his powers to municipal courts, and then to the land courts. As a result of their activity, town and land books were created. The Castle Archives functioned until the mid-17th century.