The Rice Terraces of the Philippine Cordilleras (Filipino: Mga Hagdan-Hagdang Palayan ng Kordilyera ng Pilipinas) were inscribed on the UNESCO World Heritage List in 1995, the first-ever property to be included in the cultural landscape category of the World Heritage List. This inscription has five sites: the Batad Rice Terraces, Bangaan Rice Terraces (both in Banaue), Mayoyao Rice Terraces (in Mayoyao), Hungduan Rice Terraces (in Hungduan) and Nagacadan Rice Terraces (in Kiangan), all in the Ifugao Province, the Philippines. The Ifugao Rice Terraces reach a higher altitude and were built on steeper slopes than many other terraces. The Ifugao complex of stone or mud walls and the careful carving of the natural contours of hills and mountains to make terraced pond fields, coupled with the development of intricate irrigation systems, harvesting water from the forests of the mountain tops, and an elaborate farming system.
The Ifugao Rice Terraces illustrate the remarkable ability of human culture to adapt to new social and climate pressures as well as to implement and develop new ideas and technologies. Although listed by the UNESCO as a World Heritage site believed to be older than 2,000 years, there are some conflicting studies that report they may be less than 1,000 years old. Maintenance of the living rice terraces reflects a primarily cooperative approach of the whole community which is based on detailed knowledge of the rich diversity of biological resources existing in the Ifugao agro-ecosystem, a finely tuned annual system respecting lunar cycles, zoning and planning, extensive soil conservation, and mastery of a complex pest control regime based on the processing of a variety of herbs, accompanied by religious rituals.