spontaneous choir performance in Museum Our Lord in the Attic: a former hidden church in the old center of Amsterdam, at the corner of Oudezijds Voorburgwal and Heintje Hoekssteeg. The house was bought in 1661 by the stocking merchant Jan Hartman, who had a Catholic church built in the attic. The church, dedicated to Saint Nicholas, was used for more than two centuries until the large new Saint Nicholas Church near Central Station replaced it. In 1888 the attic church became a museum. It is, aft