Imagine, if you can, over 10,000 km² (4,000 mi²) of empty, open, flat space. Visibility is clear for as far as the eye can see over the pristine, white ground. In the distance, you see a small land form. Is that a mirage? Not today—it’s the Geocache of the Week on Isla Incahuasi amidst the Bolivian salt flats.