Erected on the place of the original Romanesque collegiate church (mentioned since 1148), which was destroyed during the Mongolian invasions in the 13th century and the Lithuanian raid in 1349. In 1360 the King Casimir the Great founded a new collegiate church, which received the dignity of the Cathedral in 1818 when the Sandomierz Diocese was established, and then, in 1960, the dignity of the Cathedral Basilica. It is a Gothic building of a hall type with a trilaterally closed and extended presbytery, ceiled with a cross - ribbed vaults. The polychromies preserved on the walls of presbytery were made by the Ruthenian workshop of master Hayla from Przemyśl in 1421. The frescoes were uncovered and restored in the years 1934-1936. The altars and portals of the Cathedral are made of black marble and decorated with pink marble. They are representative examples of stone wares from the workshops in Czerna near Cracow from the 17th and the 18th century. The interior of the church is decorated with a complex of magnificent rococo altars (from the second half of 18th century) at aisle piers. They were made by a prominent craftsman Maciej Polejowski from Lvov. On the walls of the aisles there is a set of 16 paintings, of which twelve create the “Calendarium” cycle, whereas four paintings under the gallery present scenes from the history of Sandomierz, painted by Charles de Prevot between 1708 and 1737. In the treasury of the Cathedral there are: the privilege document of the town’s second location from 1286, numerous incunabula and the Reliquary of the Holy Cross Tree offered to Sandomierz Collegiate church by the King Ladislaus Jagiełło who thus acknowledged the merits of the Sandomierz knighthood in the Grunwald battle.