Deep in the Grand Canyon walk near Blackheath, Greaves Creek carves through the Blue Mountains sandstone in a series of cool, tannin-tinged pools shaded by dripping ferns and hanging swamps. The rock pools reward walkers who tackle the steep Grand Canyon circuit - one of the finest short walks in the mountains - with a place to cool off deep in the gorge. The forest here is a green, mossy world far below the plateau rim. Come prepared for the climb out; the descent is the easy part.