A Lil Sage River Question For Those Who Might Know.

Heyo, It's your friendly neighborhood Schmuel with a lil question for those who might know.

At the top of the waterfall that starts the River sage in Gavel (Next to Karoc Quarry), there is this indent in the flow of the river as seen in the image below. It says that a Breathing Helmet II is required but when approached while wearing one it repeats the same message.



Seeing as how I never took the time to fully explore gavel when it was first released I was wondering if anyone had a possible answer to where this leads. If it's just a lil den for the kappas that inhabit the River Sage or if its a little piece of the map that has been touched in a while any help would be appreciated. :D

 

You need to go in there for the quest called From the Mountains and search for an item which is needed to progress the quest.

 

Thanks for letting me know, I guess after not leveling a class for so long it just slipped my mind.
@Maki Nishikino