Chances are you’ve seen a vagina. 50% of the world's population has one. Still the vagina is like a cave of forgotten dreams. It's a mystery organ with many secrets, worthy of a Werner Herzog voice over. Think about it. How much do you really know about the vagina you’ve been sticking your penis into? Even if you consider yourself an expert in vaginal architecture (or a pussy professor, if you will) there are certainly some facts about the vagina that will still surprise you. So here, in brief, are a few things you should know about your favorite sex organ. Some of them are disturbing, some of them will make you scratch your head, and all of them will help you understand women just a little bit better.