People have lived in the area of Tempe Papago Park for at least 1,000 years. In the past, the Rio Salado (Spanish for Salt River) flowed through the Valley of the Sun, supplying water for agriculture. The people called Hohokam lived near the river and developed an extensive desert valley canal system to channel the water from the Rio Salado to their fields of corn, beans, squash, and cotton. Their system of irrigation became the foundation for the canals seen throughout the valley today.
Loma del Rio ("hill by the river") is located on the crest of a ridge on the north side of the Rio Salado. Occupied during the Classic Hohokam or Salado period (a.d. 1200-1450), the site consists of six connected residential rooms and another room set apart which was probably used for cooking. At some point the doorways in three of the rooms were sealed off and may have been converted to storage areas. These rooms could have been entered through an opening in the roof using a ladder. This roomblock had a walled plaza and an outdoor cobble-paved patio. The site might have been a residence for 15 to 20 people.
There is evidence for a network of crescent-shaped terrace gardens built into the hillside to the west and south of the roomblock. These terraces were ideal for growing agave, also known as the century plant, because agave plants required no irrigation. The Hohokam used the fibers from the leaves to weave cloth or make rope, and it would have been an important food source, especially during periods of drought.
Stone tool fragments and distinctive decorations on some of the prehistoric pottery found at Loma del Rio show archaeologists that trading was taking place with sites up to 300 miles away, such as Casas Grandes, Mexico; Mule Creek, New Mexico; and Flagstaff, Arizona. The people living at Loma del Rio would almost certainly have visited larger and more well known Hohokam communities in the Salt River Valley, like Pueblo Grande, Mesa Grande, and La Ciudad. Hohokam settlements were abandoned by about a.d. 1450.
In historic times the Pima used the abandoned ruin of Loma del Rio for a shrine, placing offerings such as Spanish glass beads. These objects, called "padre beads," were made in Spain during the 18th and 19th centuries, and were gifts from Spanish settlers and priests.
The excavation of Loma del Rio was conducted by Arizona State University's Anthropology Department over the course of three field seasons from 1984 to 1986. The Anthropology Department and the Archaeological Research Institute at ASU care for many artifacts recovered from archaeological excavations in central Arizona, and make them available for study by students and other scholars.
In 1995, the City of Tempe installed interpretive signs and a trail leading to the Loma del Rio ruins in Tempe Papago Park south of Curry Road. For a nice view of Tempe Town Lake and the surrounding valley, visit the ramada near the ruins.