i rememebr reading somewhere once that the deepest parts of the oceans are like 15 miles deep !! - imagine that - the kind of stuff that is at the bottom that we have no idea about !!
Yes, it is a hidden world, that you must explore. Well, I think that there are many pre-historic species that we don't know, living on those depths, as in the amazon forest. About the bifoot legend, I don't believe in it, as far as the loch ness monster is concerned, probably it is possible that some animal species that we don't know might live there, I have absolutely no clue if it is pre-historic or not, but I think it is worth of some money investment in technologies capable of determine all life forms that live in that lake, as well as a detailed geographic study of the region, to find any underwater caves or any kind of conection to even further depths. I think that the amazon forest is the most difficult region to explore, especially the swamps zone, it simply isn't reachable for man, no one could live there, but at this rithm of forest destruction, I say that in the next 20 years it will be possible to camp near thoses zones (unfortunatelly), and many species will be discovered on the last virgin region of this man-destroyed-planet.