Hahahahaha! I never realized Cambodia had something like this, so cool! From other pictures I've seen, I believe there's a rope you can use to get down into it and as for the shot, yeah, I think Callie has it right.
i think the photographer was lying on the ground to get this shot and the man was prolly not that high off the ground, its the angle of the camera....OR either that he's awfully giant tall, look at them long ass legs, lolz!!