The large desert located in southwestern U.S. is the Sonoran Desert. This vast desert spans parts of California, Arizona, and northern Mexico, characterized by its unique flora and fauna, including the iconic saguaro cactus. The Sonoran Desert experiences extreme temperatures, with scorching summers and mild winters, and is known for its distinctive ecosystems that support a diverse range of wildlife. It's also recognized for its stunning landscapes and scenic beauty, drawing hikers and nature enthusiasts from around the world.