Came to the end of the trail and it turned into a nice bumpy track made out of grey slate which I could see all the way to the road, about 200m's away. I let go the brakes and was playing on the bumps doing 46kmph (checked my GPS after) I suddenly saw a chain across the trail at headtube height, about 2 bike lengths ahead. It was almost invisible against the grey trail until it caught the sunlight. Braked hard but no distance to slow down so jumped over the bars and tumbled for ages, feeling the bike hit me and going over and over and over again! I don't know how but I am almost completely fine! Scraped and have a perfect imprint of half my E13 bashring on my stomach (glad it wasn't a 44t big ring!). Bike is fine too, not a scratch but I've hit the chain hard enough to completely smash the big padlock on it, the link on it is bent almost straight!
I'm still shaking my head and wondering how I got away with that. Anyone else got any similar stories?