It was neither animal nor vegetable but minerals that spawned this city of nitrate barons and opulent mansions. Marks of abundance persist at Plaza Arturo Prat, with its palm trees, clock tower, and Renaissance-style Municipal Theatre. Below the city lurks the sand dune known as The Dragon--rendered less scary by the nearby disco, casino, and beach. These marks of civilization give way fast, however, to the Atacama's vastness. Here, sands sweep around the ghost town of Humberstone and the remarkable Pintados Geoglyphs--a hillside "exhibition" of over 400 native paintings preserved by the desert for thousands of years.