Many years ago, before I was twenty, I hitched a ride on a pearling boat with a sea kayak to shoot the horizontal falls in the Kimberley (Western Australia) which was then (~1980) unvisited and well off even the remote adventure tourism tracks although much better known now [1][2].

It remains today as both one of the most exhilarating and the stupidist things I've done.

Equatorial tide changes through a narrow gorge are insane enough before adding in salt water crocodiles on one side and sharks on the other (well, both on both sides to be honest).

[1] https://www.youtube.com/watch?v=3dIhCmo3g0c

[2] https://www.youtube.com/watch?v=4xYg73DV0V0