[SunkenCiv]

subtitle, "An unmarked, overgrown path through dense vegetation leads to the largest ancient structure in Polynesia."

I'd like to point out that the structure is believed to be medieval in date, which is kinda ho-hum.

Pacific vistas DAVE LONSDALE (CC BY 2.0)

[Fungi]

https://www.atlasobscura.com/articles/found-tropical-plant
Go look for this one, please....

[blam]

What about Nan Madol?

Nan Madol

[BenLurkin]

Built by relatives of the Menehuni perhaps.

[MadMax, the Grinning Reaper]

Pulemelei for skiing or “Cool Running” practices and the other for Human Sacrifice or short bungee-jumping.

[bert]

It was almost certainly an astronomical observatory for marking the solstices and perhaps lunar events

[null and void]

to a height of 12 meters (23 feet)

New math.