Channel Islands National Park consists of five of the eight Channel Islands off the Pacific coast of the U.S. state of California. Although the islands are close to the shore of the densely populated state, they have been relatively undeveloped. The park covers 249,561 acres, of which 79,019 acres are federal land. The Nature Conservancy owns and manages 76% of Santa Cruz Island, the largest of the eight.
The islands are home to significant natural and cultural resources, resulting in several designations. Anacapa and Santa Barbara islands were made a national monument in 1938. All eight islands became a biosphere reserve under UNESCO in 1976. And five — Anacapa, Santa Barbara, Santa Cruz, San Miguel and Santa Rosa — were made constituent to the new national park on March 5, 1980. Of these, all but Anacapa are in Santa Barbara County, the latter being in Ventura County.
Channel Islands National Marine Sanctuary encompasses the waters six nautical miles around Channel Islands National Park.