Dusk of Dragon's Quest Help

[Zennistrad]

I'm in the Dragon Burial Ground and am supposed to "clear a path between caves," but I've explored all of what I can find in the caves and there's nothing here but a bunch of spiders. There was one place where I could perform an athletics check, but that just leads to an isolated chamber with some extra loot.

What do I do here?

[forkofspite]

* take a left at the first set of spiders (same place where that first athletics check was)
* push the bridge down (athletics check)
* cross the bridge and turn right
* slight left and move some rubble (mobility check, for some reason)
* explore beyond where the rubble