Open house at Posthoornkerk and Oosterkerk. Visit the Posthoornkerk and Oosterkerk every third Sunday of the month between 12:00 and 16:00. Our volunteers are happy to talk to you and tell you more about the history and architecture. Stadsherstel has several monumental buildings, including some Special Locations. Through creative repurposing and opening, these monuments remain open to the public and Stadsherstel can preserve this cultural heritage. Other openings: De Duif, Posthoornkerk, Oosterkerk and Vondelkerk are also open every first Wednesday of the month from 12:00 – 16:00. The Bakenesserkerk is open every third Sunday of the month from 12:00 – 16:00. Check our culture agenda for the latest updates and exceptions.