Rujm

"Rujm" is a word that comes from Arabic and it means "pile" or "stone heap". Imagine playing with your building blocks and making a pile of stones or Lego bricks. That's what a rujm looks like, except it's usually made of big rocks and it's outside, not inside. People actually made piles of stones on purpose a long, long time ago, thousands of years ago. They made them in the desert or on top of a hill or somewhere special. The reasons they made them are not always clear, but some people think they were used for things like marking important places, or as tombs for important people. Nowadays, some rujms are still around and people go visit them to try to figure out what they were used for.