Wanderlust World Wanderlust World Baja California is a peninsula in northwestern Mexico—not a U.S. territory. It stretches ~775 miles (1,250 km) from the U.S. border at Mexicali/Tijuana to Cabo San Lucas, separating the Pacific Ocean (west) from the Gulf of California/Sea of Cortez (east).
Width varies from 30-150 miles. The peninsula is arid to semi-arid—Sonoran Desert in the north, vizcaíno Desert centrally, tropical deciduous forest at the cape. The Gulf side is generally calmer and warmer; the Pacific side cooler with surf beaches.
Baja California is entirely Mexican territory. The U.S. states of California, Arizona, and New Mexico border it to the north, but the peninsula itself has never been U.S. territory. The 1848 Treaty of Guadalupe Hidalgo established the current border at the Colorado River/parallel 32° north.