I once spent a whole afternoon in the sun without any sunscreen. Got blisters and the nerves in my back when nuts. It felt like thousands of very fine needles being poked into my back very rapidly. Evidence that I'm not as bright as I'd like to be.
Four years ago I volunteered to sit in a dunk tank at my town's festival we have every late June (actually this week) and being of an officer rank in the Fire Department and annoying enough underlings I became a prime target. Well, it turned out everyone else that had signed up for that duty bailed on it, and I sat in that dunk tank for six hours in direct sunlight.
I was burnt so bad the skin peeled off my hand like a glove and I needed IV fluids.