The 139-mile Larapinta Trail hits its high point in West MacDonnell National Park, at a 1,640-foot bluff that overlooks soaring rock walls, folds of red desert, and swooping wedge-tailed eagles. "Waking up here is the most solitary, top-of-the-world feeling," says bush guide and biologist Shane Fewtrell. An end-to-end trek is a rigorous 20-day undertaking; hikers can go days without encountering a soul (from $2,780 for a fully outfitted trek led by Fewtrell; treklarapinta.com.au). Or tackle a shorter segment on one of Fewtrell’s six outfitted section hikes of ridge hopping and gorge plunging (six days, from $840; nine days, from $1,300).