Oude Kerk is aptly named. It is the oldest church in Amsterdam. The wooden church from 1213 was replaced by a stone structure in 1306. Modifications and extensions continued through 1460. The roof has the largest medieval vault in Europe. The floor is covered with gravestones. Beneath them are about 10,000 bodies. The footprint is a massive 36.000 square feet. The original denomination of Oude Kerk was Catholic. It was converted to the Dutch Reformed Church during the Protestant Reformation in the late 16th century. You can climb this clock tower during a guided tour. Music from the carillon is performed on Tuesdays and Saturdays at 4:00 pm. Ironically, Oude Kirk is located within the Red Light District.