The Gulf of California (also known as the Sea of Cortez, Sea of Cortés (named for Spanish Conquistador Hernán Cortés) or Vermilion Sea; locally known in the Spanish language as Mar de Cortés or Mar Bermejo or Golfo de California) is a marginal sea of the Pacific Ocean that separates the Baja California Peninsula from the Mexican mainland. It is bordered by the states of Baja California, Baja California Sur, Sonora, and Sinaloa with a coastline of approximately 4000km. Rivers which flow into the Gulf of California include the Colorado, Fuerte, Mayo, Sinaloa, Sonora, and the Yaqui. The gulf's surface area is about 160000km2. Depths range from fording at the estuary near Yuma, Arizona, to in excess of 3000m in the deepest parts. The Gulf is thought to be one of the most diverse seas on the planet, and is home to more than 5,000 species of micro-invertebrates. Home to over a million people, Baja California is the second-longest peninsula in the world, after the Malay Peninsula in Southeast Asia. Parts of the Gulf of California are a UNESCO World Heritage Site.
