I lost count of the visits I have made at the world's famous "Underground River", but I can vividly remember that those visits stirred up my desire for more.
The river runs through an amazing 8.2 kilometers long navigable cave. It is nestled under the mountain covered with the thick canopy of trees. As you enter its mouth, hundreds of bats and swallow birds will greet you. Amazing natural rock formations like the cathedral, giant mushroom, giant melting candle, glittering stones, and the intertwined stalactites and stalagmites will make you gasp in awe.
There's also a bonus part of communing with the park's monkeys and monitor lizards at the picnic area. My best experience so far, was when the monkey literally came up to me and snatched the mango out of my hand. Poor me, happy monkey!
And if you want more adventure and adrenaline rush experience, you can take the monkey trail instead of the boat. This will entail physical stamina because you will be trekking up and down the mountain. The trail holds a unique nature experience that you will remember for a lifetime.