Once, when climbing a 7-pitch route in Switzerland, the party below us involuntarily removed a loose block (mostly held in place by vegetation), maybe 30x30x50c

Once, when climbing a 7-pitch route in Switzerland, the party below us involuntarily removed a loose block (mostly held in place by vegetation), maybe 30x30x50cm. We had noticed that it was loose and it had a sling fixed next to it as a replacement hold but apparently they didn’t realise. Thankfully nobody was standing below. Super scary though.