This was pretty hard to find, and I guess during the Nazi occupation, that was the idea, as it was a hidden church, so from the outside it just looked like a house. From what we remember the outside sign just said 'Our Lord in the Attic Chapel', and not Amstelkring Museum. We enjoyed visiting and really only takes 30 minutes or so. Free with the I Amsterdam card, which in itself is worth it if staying a few days and you plan on visiting museums and galleries.
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