Riverside County and San Bernardino County to the north form this metro area. Like many such metro areas in the Southwest, it extends far into uninhabited desert areas, in this case east through the Mojave Desert to the Nevada/Arizona border. Larger than nine U.S. states, it is often referred to as the Inland Empire. Cities in the western portion, including Riverside, San Bernardino, Ontario, and a patchwork of other communities, are developed suburbs of the Los Angeles area with a rapidly growing and increasingly self-sufficient economy.

Suburbs along the I-10 corridor, including Ontario, Rancho Cucamonga, Fontana and Colton tend to be more commercial, while others off the main roads and against the area’s many mountain ranges, like Loma Linda, Chino Hills and many parts of Riverside are more residential. Ontario is also the site of one of the LA area’s best airports with considerable discount air service. Old mansions, public buildings, and packing sheds serve as evidence of the orange-growing industry that once dominated the area, but these have been long since surrounded by housing developments, industrial parks, and commercial/retail centers. Farther east through a mountain gap lie the resort communities of Palm Springs and Palm Desert.

Today the main economic activities include a host of diversified light manufacturing, international trade and offices of overseas companies. Although rising rapidly, costs of living and housing remain relatively affordable for comparable areas in Los Angeles and Southern California. The area is now facing many of the same issues confronting Los Angeles as a whole- overcrowding, sprawl, poor air quality, and long freeway commutes. Bottom line: this area offers many Southern California advantages while bringing the negatives in somewhat smaller doses.

The area is semiarid to arid with dry valleys surrounded by desert mountain ranges. Most of the valley floor to the west is developed. Moving east, coastal grasses and brush give way to desert foliage, including brush, creosote bush, and cactus. The climate varies by altitude and distance from the Pacific Ocean. Summers are warm in the western portion of the counties to extremely hot and dry eastward. Evenings, consistent with the desert climate and with some marine cooling, are comfortable. Winters are mild and mostly dry, but most annual precipitation, including rainy spells, occurs during this season. There are a few days each winter with below-freezing temperatures, but many winters are frost-free. Snow is rare but can occur.