Waimea is a census-designated place 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 US Post Office name for Waimea is Kamuela.Waimea is the largest town in the interior of the Big Island, and 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, 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.