Posthoornkerk Posthoornkerk, Haarlemmerstraat (front) Posthoornkerk: Haarlemmerstraat 124-126, 1013 EX Amsterdam In the middle of the city, on the bustling Haarlemmerstraat, is one of the most important surviving nineteenth century churches in Amsterdam. The neo-Gothic Posthoornkerk with its three slender towers is an eye-catcher in the city center. The catacombs of the Church are home to the Geelvinck Early Piano Museum, Amsterdam– a space where musicians of the Conservatorium of Amsterdam can practise and learn on historic pianos. Covid-19 protocol Posthoornkerk