The Sacred City of Caral or Caral-Supe is the capital of the Norte Chico Civilization of Supe located in the Supe Valley, 200 km (124 miles) north of Lima. The Sacred City of Caral is the earliest known civilization in the Americas, it dates to the Late Archaic period. Radiocarbon analysis performed by the Caral-Supe Special Archaeological Project (PEACS) dates its development between 3000 to 1800 B.C.. It is believed that this civilization started by the merging of small villages based on trade of agricultural and fishing products. Its importance rests on the success of techniques of domestication of cotton, beans, potatoes, chilis, squash among other products. Success in agriculture was due to the development of water canals, reservoirs and terraces. They used guano, bird excrement, and anchovies as fertilizer.