29. Lidenbrock Sea
As a scientist, I am supposed to believe that under the Earth's crust is a huge volume of mantle rock. Jules Verne, in his book 'Journey to the Centre of the Earth' says that no, under the Earth are oceans lit by phosphorescent algaes, giant mushrooms, seas of thick seaweed, lost tribes, dinosaurs, lost explorers, discarded diaries and maps etc etc.
Verne's version is better. And in the movies, lost tribes is best visualised by nubile cavewomen with acres of flesh, perfect for Doug McClure (Troy?) to grab on to during his many, many whistlestop tours of the underworld.