Almost two years ago, I made the mistake of going to the beach in Australia at midday and not covering up sensibly. I put lotion on when I got there, but not enough, and I didn't have a hat or anything. I was so badly burnt my face was pink for days and it swelled up.
About two years ago, I forgot to put on sunscreen, then spent the entire day at the waterpark in 90 degree weather, and a day later, I had burns ALL over my entire back and neck. I still have scars from them, I think.