The Oude Kerk, a church standing strong since 1306 and located in Amsterdam, is a fascinating blend of contradictions. On one hand, it is an active house of worship; but on the other, it is surrounded by the notorious Red Light District. Inside, visitors will find a Vater-Müller organ, 15th-century carvings on the choir stalls, and the graves of famous Amsterdammers, including Rembrandt's wife, Saskia van Uylenburgh. Not to mention, it has regular art exhibitions and a guided tour up the tower. The only requirement for admission is that visitors pay by credit/debit card.