This art piece by Polish artist Mirosław Bałk is a commentary on mass tourism, which was inspired by a Krakow tour agency offering visits to the Auschwitz-Birkenau concentration camps and the Wieliczka salt mines in eight hours. The words AUSCHWITZWIELICZKA appear on the interior and moves from wall to wall as the day progresses.
I picked this piece as an entry since I thought it to be a little different. Usually the shadows themselves are the primary focus but in this case the surrounding shadows are secondary and the focus is on the word created by the absence of shadows.