driving on water.. I want to know, is there a speed that any vehicle must attain in order to drive on water? Or, is it a mix of tire size, tread, air pressure, rpm per tire, 4 wheel drive, and then weight of vehicle plus the speed before the vehicle gets to the water?

wouldn't it be right to call these the only real ATV? They seem to be all terrain, and even on water... I've seen them drive up those Iceland cliffs too