Panama's legendary Darien jungle has defeated the Pan-American Highway and numerous attempts to tame its pristine wilds. But, as loggers and settlers close in, one of the world's richest wildlife habitats is headed for the buzz saw, reports a DEET-slathered Scott Doggett.

DARIEN NATIONAL PARK, PANAMA -- Stumps, chuckholes, vipers and foliage have fogged into a brown-green blur. Eight river crossings have soaked through the duct tape I've wrapped around my feet to avoid what's now happening.

Led by Hernan Arauz, the son of Panama's foremost explorer, I've come to retrace the old gold route through one of the most formidable slices of jungle in the hemisphere and witness the forces gutting this once-forbidden realm. With each step, blisters ignite and mortal ambitions falter.