Arizona-Sonora Desert Museum

William Carr and Arthur Pack opened the Arizona-Sonora Desert Museum on Labor Day 1952, in the Tucson Mountains west of the city. What they built holds more than 230 animal species and 1,200 plant varieties — zoo, botanical garden, and natural history museum at once, organized by the desert's own logic rather than by institution. The early board included naturalist-author Joseph Wood Krutch and paleontologist Roy Chapman Andrews. Around 400,000 people make the trip each year.