ED:
YEAH!
ME!
If you're talking about a large cavern that has
two (2) entrances to it
One at ground level,
the other from way up on the top!
(The top of the cavern/canyon)
If you had mentioned this, when we were last in The Bradshaw Mnts
AND!
I would have related the story to you!

But!
Here is a "brief" description about it
It was Used, for sure by The Apaches and Maybe by The Spanish
There appears to be "chests", boxes, weapons, stacks of bars & etc inside
Put there by ? Spanish ? Apache ?
This
was seen by a friend of John Ballinger, who found The Upper entrance
But!
Never got into the cavern
I know that's not much information
But!
I don't want to reveal too much here on "The Net" !
Does this sound like want you interested in?