Between around 600 BCE and 850 CE, a civilization known as the Aquiry transformed swaths of southwestern Amazonia, carving enigmatic geometric earthworks into the landscape. "It completely transformed my understanding and made me realize how mistaken earlier assumptions had been. (Martti Pärssinen, supplied)The Aquiry civilization wasn't a single kingdom or empire, but a diverse network of communities connected by shared traditions. What we do have are their monumental earthworks: geometric spaces delineated by ditches that could be meters deep, linked together by straight roads, where people may have gathered for ceremonies and political events. Today, the geometric earthworks and the ecological legacy of their land management are among the few visible traces the Aquiry left behind.