Saguaro National Park is named after the giant species of cactus it was originally established to protect. It is now one of the largest preserves in the United States for this iconic symbol of the American west. It is split into two separate regions -- called districts -- on either side of Tucson, Arizona. Each district is on the outskirts of town, making this an easy park to access from a major metropolitan area. Kristi and Ray from San Francisco joined Greg on this trip. This was their first trip to the desert.