New Zealand: Tongariro Alpine Crossing

 Red Crater at the highest point of the Tongariro Alpine Crossing. 

 You gaze down on Emerald Lake as you slide walk down loose stone and dirt. It's a bit like descending a sand dune or scree field. 

The Tongariro Alpine Crossing is considered by many the best day hike in New Zealand. It is certainly a tough one. Great views in an interesting area compete for your attention with the hordes of people tramping the trail with you. It is a hike of extremes.