The sprawling site, which has now crumbled into dust, sits deep in the heart of Thailand among on the picturesque tropical hills of Kanchanaburi.
The once-booming business fell into disrepair in 2005 after being muscled out by competitors, leaving algae to fill the pools and plants to creep into every crevice.
Urban explorer Dax Ward, 38, said he was drawn to the post-apocalyptic landscape – but he didn’t realise how dangerous it was until he ventured inside.
He said the park held a dark past as it was once the site of a brutal murder-suicide and now plays host to nefarious characters lurking in the night.
“I definitely don’t want to encourage others to try this,” the US explorer said.
“From the broken metal and glass, to the insecure foundations on upper floors and death-trap escalators, it’s a very dangerous place.
“Then there’s the nefarious characters that have nothing better to do than hang out at a large creepy abandoned site in the dark.
“You probably don’t want to be around then, lest you enjoy being stabbed with something rusty.”
While the park once welcomed crowds from far and wide, the only occupants now are the local wildlife and shadowy characters.
In 2010, the water park reportedly became the scene of a heinous crime when a mentally ill man murdered his wife and himself.
Mr Ward said the dark past still hung heavy over the park – and he wouldn’t dare step foot in the site after dark.
“It was pretty creepy to think of what happened in the waterpark,” he said.
“I didn’t learn of the murder until afterwards, but I got a very eerie feeling in there even without knowing of what had happened.
“I definitely got the sense this is not the kind of place you want to visit after dark.”