TRL: Another hole into the underworld

This one's in first area in Peru (the training-dummy area). You fall
forever. Nothing too great, therefore.

Anyway. To describe where it is, for those who like these things...

Get on the roof and grapple-swing to the building directly across the
street, the way you do when you go for that first Bronze. On that roof look
across the courtyard (in the same general direction) to the next building
down the street. Aim Lara at the little alley way between that building and
the one to the left of it. Run/jump. You'll pass through stuff and fall
(forever; time to reload).

I found this one by throwing the grapple at things. Invisible walls stop
the grapple. When the grapple continues on into the distance without
hitting anything, you know there's no invisible wall in the way.

--cleve