Casimir was buried in the crypt under the Royal Chapel of Vilnius Cathedral (present-day Wołłowicz Chapel to the left from the main entrance), constructed by his father in the Gothic style in 1474. In 1604, the coffin was elevated from the crypt to the altar and in 1636 moved to the dedicated Chapel of Saint Casimir. The present-day sarcophagus was made in 1747 under the last will of Bishop of Warmia Christopher Johan Szembek (1680–1740). It is made of linden wood and covered with silver plates; its corners are decorated with gilded eagles. The sarcophagus was removed from the cathedral on three occasions. In 1655, before the Battle of Vilnius during the Deluge, the relics were removed most likely by Jerzy Białłozor and hid by Cyprian Paweł Brzostowski and later by the Sapiehas in the Ruzhany Palace. They were returned to the devastated chapel in 1663. The relics were removed for a short time in 1702 during the Battle of Vilnius of the Great Northern War. In October 1952, the relics were quietly moved to the Church of St. Peter and St. Paul by the order of Soviet authorities. The cathedral was turned into an art gallery. The relics returned to their place in 1989 when the cathedral was reconsecrated.