Gevelstenen / Facade stones
Gevelstenen are bas reliefs, most often rectangular or square, placed on the facades of many Dutch homes. Many date back to the 17th century; others are newly made. They have fascinated and delighted me for years.

By the way, there is a Flickr group page devoted to Gevelstenen:

Note that there is a remarkable Flickr site devoted to such facade stones in Amsterdam:
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