one of the Channel Islands, 22 miles (35 km) off the Pacific Coast of California, U.S. The largest of the Santa Catalina group of the Channel Islands, it is 22 miles long and 8 miles (13 km) across at its greatest width and has an area of 74 square miles (192 square km). It rises to Mount Orizaba (2,130 feet 【649 metres】 above sea level) and has pine forests and chamise chaparral vegetation. It is administratively part of Los Angeles county.

The island was discovered by the Portuguese navigator Juan Rodríguez Cabrillo (Cabrillo, Juan Rodríguez) in 1542 and in 1602 sheltered a Spanish sea expedition led by Sebastián Vizcaíno, who named it on the feast day (November 25) of St. Catherine (Catalina) of Alexandria. Deeded to the United States in the Treaty of Guadalupe Hidalgo (Guadalupe Hidalgo, Treaty of) in 1848, it developed as a resort after it was purchased by chewing gum magnate William Wrigley, Jr. (Wrigley, William, Jr.), in 1919. Avalon (incorporated 1913), the island's only city, is connected by boat and air services to San Pedro and Long Beach on the mainland. A seal colony, evening boat trips to view flying fish, and submarine gardens are attractions on the island that draw millions of visitors each year.