California contains a valley.
California . California 's diverse geography ranges from the Pacific Coast in the west to the Sierra Nevada mountain range in the east ; and from the redwood -- Douglas fir forests in the northwest to the Mojave Desert in the southeast . The Central Valley , a major agricultural area , dominates the state 's center . The Klamath Basin is the region in the U.S. states of Oregon and California drained by the Klamath River .