Lying between the Coast Range and the Sierra Nevada mountains, the Central Valley is the agricultural heart of California. Most communities lie along the current or historic route of California highway 99, which in some portions has been subsumed by I-5. The major cities defining the ends of the Central Valley are Redding and Bakersfield; the region also includes Sacramento, Stockton, Modesto, Fresno, and Visalia. The Central Valley is composed of two valleys: the Sacramento Valley north of the San Joaquin River Delta and the San Joaquin Valley south of it.