The Castle of the Masovian Dukes is a medieval Brick Gothic castle located in the village of Czersk (36 km south of Warsaw), Masovian Voivodeship, in Poland.

The Czersk Castle was built at the turning point of the fourteenth and fifteenth century by Duke Janusz I, after the Masovian land became part of the Kingdom of Poland under the rule of Queen Bona Sforza.

[2] In 1656, during the war with the Swedes, the castle was partially ruined, when the retreating land army under Stefan Czarniecki's command had captured and demolished the stronghold.

In the years to follow, no more reconstruction work on the castle had ever been attempted.

Today, only the towers, a brick bridge from the eighteenth century, and the north and east wing of the castle remain of the overall stronghold.