The brainchild of groundbreaking architect and urban planner Paolo Soleri, Arcosanti is a desert outpost based on 'acrology': architecture meets ecology. This cross between a kibbutz and design school 65 miles north of Phoenix looks like a village on Luke Skywalker's home planet. Radical when conceived in the 1960s, Soleri's ideas now seem cutting-edge in this age of urban sprawl and global warming. Arcosanti is good for a day trip or a long stay - there are week- and month-long seminars, a café, one-hour tours, concerts and other events. Basic accommodation is available, and the Sky Suite is designed for great views of a dark desert night.