Australia's Uluru (previously known as Ayers Rock) lies in the middle of a desert that feels rain as little as three days every year. So I felt fortunate that I happened to be there on one of those days. The top of the rock is so vast and flat that rainwater cannot collect. Therefore, all the water falling on Uluru's 3.3 square kilometers gushes toward, then down, the sides, resulting in countless waterfalls that last only as long as the storm.