Waimea is a census-designated place (CDP) in Hawaiʻi County, Hawaiʻi, United States. The population was 7,028 at the 2000 census and 9,212 at the 2010 census. Since each U.S. state cannot have more than one post office of the same name, and there is a post office in Waimea, Kauai County, the official U.S. Post Office designation for Waimea is Kamuela, although this name is only used by the post office, not by locals or the local government. The name Waimea means reddish water.
Waimea is the center for ranching activities and paniolo culture. The Parker Ranch in and around Waimea is the largest privately owned cattle ranch in the United States, and the annual Fourth of July rodeo is a major event. The Waimea Cherry Blossom Heritage Festival, held annually in the first week of February, has recently become another major event of the town. In the center of town are the Isaacs Art Center, the Wishard Gallery, Paniolo Heritage Center at Pukalani Stables, and the Gallery of Great Things, all featuring Hawaiian art.
Waimea is home to the headquarters of two astronomical observatories located on Mauna Kea, the W. M. Keck Observatory and the Canada–France–Hawaii Telescope. It is also headquarters of the International Lunar Observatory Association.
Waimea also is the home of Hawaii Preparatory Academy and Parker School (Kamuela, Hawaii), two of the top independent schools in Hawaii.
It is believed that the watershed area of the Kohala mountains once supported several thousand native Hawaiians, who practiced subsistence agriculture, made kapa, and thatched dwellings. As the Europeans arrived in the area, most of the sandalwood (Santalum ellipticum) forests were harvested and the land became ideal for grazing animals.