I was on a MUP that I hadn't been on in a long time and came around a corner to a wooden bridge. It was raining so it was wet and slippery. I couldn't stop before I got to it and as soon as I hit it my wheels went out from under me. I still have the bruise on my thigh where I bounced off the wet muddy bridge. Hit hard enough to jar an old spine injury I got while snow boarding. I just sat there for a bit till the shock wore off.