Once a modest wooden chapel, built by 13th-century fisherman where the Amstel empties into the IJ River, the Oude Kerk (Old Church) is now an icon of Amsterdam. Over the centuries, successive additions to the church expanded its footstep, and now the one-time chapel dominates its own square, the appropriately named Oudekerksplein (Old Church Square), in the middle of De Wallen.
The Oude Kerk is also a focal point in the Miracle of the Host, an event said to have occured in the nearby Kalverstraat in 1345. After a Catholic priest had administered the last rites of a moribund man, the man vomited up the "host", or communion wafer; to dispose of the mess, it was thrown into the fire, host and all. But the host remained intact amid the ashes, and not only that: when twice it was transported to the parish church, each time the host was miraculously discovered back at the man's home on the Kalverstraat. The "miracle" is commemorated yearly at the "Silent Walk", a procession whose route takes in the landmarks of Amsterdam's Catholic community.