Transportation
The mountains form a natural barrier between the fast-growing Inland Empire region to the east and the job centers of Orange County to the west. Only one freeway, the Riverside Freeway (State Route 91), one tollway, the 241, and a narrow and winding mountain highway, the Ortega Highway (State Route 74), connect the regions. Highway 91, which follows the Santa Ana River through a pass between the Santa Ana Mountains on the south and the Chino Hills on the north, is one of California's most congested routes. Because of this, several proposals have been floated to dig a highway tunnel through the Santa Ana Mountains, although the multi-billion-dollar idea has drawn criticism from environmentalists and others concerned about cost and safety in the earthquake-prone region. While Highway 91 is one of the most congested routes in California, Highway 74 holds a more ominous claim to fame - one of the most dangerous highways in the state.
Read more about this topic: Santa Ana Mountains