[[Wan actually took some time to think about that before answering.]]
It doesn't move a lot that I know of, but the Lion Turtle is really strong. And I'm not sure a city really weighs that much more than it's shell and the forest that grows on it. And I don't actually know what the Lion Turtle eats. But It must eat something. I mean, it's been around forever and is still able to move and talk and everything.