The bell inside the Zuiderkerk tower was made by the brothers Willem and Jaspar Moer in 1511. It originally hung in the Oude Kerk, and it still rings to this day. Guided tour In spring and summer (April to September), and can climb the Zuiderkerk tower as part of a guided tour. Tours can accommodate groups of up to 15 people, and they take about 30 minutes. The church itself is open to the public and you can explore the interior and exhibits without a tour guide.