California is a state located in the western United States, bordering the Pacific Ocean. The most populous and third largest state in the U.S., with a population roughly the size of Canada and one of the biggest economies in the world, California is more like a country than a state. California is both physically and demographically diverse. The state's official nickname of "The Golden State" is often thought to be a reference to California’s 1849 gold rush but is in fact reference to the native grasses that turn a golden color during the dry season. California's U.S. postal abbreviation is CA, and its Associated Press abbreviation is Calif. Southern California is highly populated, while the larger northern California is less densely populated. The vast majority of the population lives within 50 miles (80 km) of the Pacific Ocean. California dominates American culture and economy, contributing significant advances in technology and legal reform, in addition to paying significantly more to the federal system than it receives in benefits. The entire region originally known as California was composed of the Mexican peninsula now known as Baja California and the land in the current states of California, Nevada, Utah, and parts of Arizona and Wyoming, known as Alta California. In these early times, the boundaries of the Sea of Cortez and the Pacific coast were only partially explored and California was shown on early maps as an island. The name comes from Las sergas de Espladián (Adventures of Spladian), a 16th century novel, by Garci Rodríguez de Montalvo, where there is an island paradise called California. (For further discussion, see: Origin of the name California.)