Some of you have been swimming in Mexico in a spring called "Media la Luna."
Here is a very good video of some skin-divers poking around in the cave at the bottom of the spring. I don't know how many divers have died here? http://www.youtube.com/watch?v=jk3v8cIf5m4 Set the resolution to high if you have a fast connection. It doesn't look like they ever left the twilight zone, but still they didn't look prepared for an emergency. I highly recommend you take a dip in this spring if you are ever in the town of Rio Verde, San Luis Potosi. David Locklear
