The caves are mostly famous for the hundreds of thousands glow worms who live in them. These worms create a astonishing sight, that may be described as a sky full of bright blue stars. It is possible to see glow worms in other places in New Zealand, but there is no doubt that in no other place the sight is as beautiful as in Waitomo.
The caves are also famous for the underground river that allows travelers to take a boat to view the worms.