These monuments are called Stolpersteine ("Stumbling Stones"): https://en.wikipedia.org/wiki/Stolperstein https://en.wikipedia.org/wiki/Stolperstein There are

These monuments are called Stolpersteine ("Stumbling Stones"): https://en.wikipedia.org/wiki/Stolperstein https://en.wikipedia.org/wiki/Stolperstein There are tens of thousands of them now, every one of them installed by the artist who originally came up with the idea. They are installed in front of their last place of residence. So it's really decentralised, and the realisation that the Holocaust happened in your street (or even to people living in the house you now life in) is powerful.