This is one place for eco-tourism. It is a good drive from Puerto Princesa but the sights along the way and the place itself is worth the trek. Bring water. Wear comfortable shoes.

its called cleopatra's nipple. not cleopatra's needle. we saw this mountain formation along the way to the underground river. this one was called so because it looks like that, a nipple. its a good conversation piece. they have a name for several mountain formation. these help keep the almost 2 hour trip to the river lively, but it depends on the guide. our guide was good at explaining. not so with our group riding on the other 2 vans.