California's Coastal Region stretches more than 800 miles along the west side of the state. Even though it is a single region of a single state, the climates of the northern and southern regions of California's coast are very different.
Most of California's Coastal Region is rocky with chilly waters. Sandy beaches and warm surf exist only on the state's most southern coast. The San Francisco Bay, on the state's northern coast, is the largest landlocked harbor in the world. The mountain range that separates the Coastal Region from the Central Valley, called the Coastal Range, is considered a low mountain range as it is compared to the Sierra Nevada mountain range farther east.