Dating from the first half of the 17th century, this large and fairly unassuming church built at the behest of Kristupas Radvila II is more famous for what lies underneath it than for anything found inside. The interior is almost bare, with a few remaining examples of gorgeous carved woodwork including a magnificent oak Renaissance pulpit. Under the floor are several beautifully restored caskets containing the remains of the extraordinary Radvila family who once owned the town.