 Although it is a dry region, the large area of these domes collects a lot of rainwater, which runs off in steep waterfalls during rain.From a geological point of view, analysis of Uluru-Kata Tjuta and Watarrka National Parks reveals an awe-inspiring history.500 million years ago, the entire area was covered by an inland sea and over many centuries, sand and mud fell to the bottom of the sea, creating rock and sandstone.