1000+ giant rectangles in the Saudi desert that predate the pyramids — and we still don't know what for

This one creeps me out in a quiet way. Northwest Saudi Arabia, the AlUla region. From the air there are these enormous low stone rectangles — Arabic mustatil, literally 'rectangle.' Some over 1,500 feet long, narrow, with a thick 'head' wall at the high end and a skinny doorway at the other. Over a ……