This paper looks at the agricultural heritage potential of the tameike reservoirs in Japan, through a case study of the Kunisaki Peninsula, which was recognized as a Globally Important Agricultural Heritage System (GIAHS) in May, 2013. The “tameike” in this area are small scale ponds storing spring water or water flowing through the short and rapid rivers of the area. Tameike construction in Kunisaki is found to be closely associated with the spread of wet rice cultivation and forestry. Most existing reservoirs were built during the Edo Period (1603–1867), and were managed through traditional farming knowhow till the postwar period. However, rapid decline in the use and ecosystem functions of these reservoirs ensued from the years of economic development, and at present, total number of these reservoirs has fallen to nearly one-third, compared to the pre-Meiji time. The GIAHS initiative is trying to reevaluate the ecosystem functions and knowledge systems associated with these reservoirs and link them to rural revitalization efforts. This article is based on both literature survey and field based research with regional coordinators, and comes to the conclusion that proper management of these reservoirs can successfully reinvigorate a culture of resource circulation, that defined the agri-heritage of Kunisaki area in historical times.