The chapel has been in use since 1857, when Walentyna Mniewska was buried, and 6 years later her husband Feliks. After restoration in 1969, the exhibition of the Battle of Bzura Museum was opened in the mausoleum, and the ashes of soldiers were placed in the basement of the crypt. Currently, the Museum is closed until further notice, and the exhibition was moved to the newly opened Saxon Palace.