From Seattle, head southeast and pick up Route 169 toEnumclaw-Franklin Road. Five miles down, you'll find some unmarkedtrailhead gates. See the gate leading toward the power lines? That'sthe Mercury Mine trail. It drops you at the edge of the Green RiverGorge, a 300-foot-deep gash. It's only 27 miles from the city, but youwouldn't know it from the Class IV whitewater (River Recreation;riverrecreation.com) and old hunters' paths in the damp primeval forest.