The foundation stones of this fine Gothic basilica were laid in 1413, under the aegis of Vytautas. Its exterior is plain, both in form (fine Gothic apertures) and ornamentation, but the interior is extremely elaborate, embellished by Renaissance and Baroque features. There are nine altars beneath its superb vaulting, including a remarkable, large 18C Baroque altar depicting the Twelve Apostles. There are also ten paintings by Michele Elviro Andrioli (1836-93).