Originally posted by Anarky:

The big rim coming closer wasn't a larger clue?

Alas, this isn't the Disc and we are not Rincewind. There's no spell that will teleport us back onto dry land.

I would be interested to see if there is a turtle over the edge though.

Me too, when I went over the edge (on purpose) I was hoping to see 4 elephants and a giant turtle. That would have been pretty cool! But, copyright issues I guess.