On the way to Monument Valley from Flagstaff, AZ, one can find ruins of Indian dwellings at the Wupatki National Monument. In 1064 AD, the Sunset Crater Volcano erupted throwing ash and minerals all over the place. The land a little further north of the area saw a rather huge influx of people that began farming. The eruption helped increase agricultural productivity by increasing the ability of the soil to retain water. However, the early 13th century saw people leaving the place and what remains today are scattered ruins of ancient dwellings.