If you're running Linux there's a reasonable chance you already have zstd installed. If you somehow don't in Debian, try apt-get install zstd

zstd -d tiles.tar.zst

tar -xf tiles.tar

This gives you a directory named tiles-backgrounds that is 1.3GB and has 12042 files. Most are tiny but others are quite large.

Looking at these, I suggest sorting my size and browsing with your preferred image browser such as Irfanview, Eye of Gnome, or Gwenview.