Seems like a terrible thing to do - imagine if they had done this on Uluru. Well, this was all about water which is a rare and precious commodity in most of Australia. The wall was built to funnel the run off from the large surface area of this rock into a dam that had been built next to the rock. It used to be the main source of water for the town of Hyden in the early part of the 20th century but is now used only for stock.