The US state of Arizona is one that features a fantastic diversity of landscapes and areas of geological interest. North Arizona is famous for the Grand Canyon, a colourful chasm with steep rocky walls more than a mile deep and stretching some 277 miles alongside the Colorado River. Other notable destinations in North Arizona include Flagstaff set alongside the San Francisco Peaks which has the largest ponderosa pine forest, Museum of Northern Arizona, and is close to a number of national parks and monuments. On the south side of Arizona lies the city of Phoenix, the largest in Arizona. Notable day trips in Phoenix include the Heard Museum which is one of America's largest collections of Native American art, Phoenix Museum of History, as well as the Desert Botanical garden which has a great collection of desert plants.