Down to the crag
As the trainee instuctor i was at the bottom of the crag belaying a child on a bottom rope system up the VDiff on the far right of the crag. (The 1st climb you see when you walk down to the bottom of the crag). His brother was sitting on a big boulder beside us when it suddenly gave way, rolled and jumped a little in the air. Leaving white markings on the rock ( you can see these if you go there) ( in pictures) Luckily the boulder rolled to the left and he jumped to the right. He jumped out the way and did a little tumble down the rocks, luckly not injuring himself apart from a scratch. We were lucky no one else was there or it could have led to a major incident.