The first and, for many years, the largest commercial airline to serve Las Vegas, Western Air Express was instrumental in putting Las Vegas on the commercial airlines map. Las Vegas had the good fortune to lie on a natural air route between Los Angeles and Salt Lake City.

In 1925, the federal Kelly Act spurred the growth of U.S. air travel by creating a national network of airmail routes to be operated by private couriers.

Western Air Express, a new Los Angeles-based company, won a contract for Airmail Route Four, connecting Los Angeles and Las Vegas with the central transcontinental route at Salt Lake City. Founded by Los Angeles auto dealer Harris M. "Pop" Hanshue, Western Air Express was one of many that took advantage of ex-World War I pilots and mechanics seeking civilian jobs in aviation.

On April 17, 1926, pilots in Los Angeles and Salt Lake City pulled on coveralls and goggles, strapped on revolvers, and climbed into the open cockpits of two new Douglas M-2 biplanes. Stopping to refuel and pick up mail at dusty Rockwell Field in Las Vegas, they completed their flights in a leisurely eight hours. Flying instructions were simple: stay to the right of the railroad tracks to avoid colliding with the plane headed in the opposite direction.

Carrying mail made the flights profitable, but the federal law's long-range objective was to develop passenger service. WAE adapted the M-2's five-foot mail compartment to hold removable chairs for two parachute-toting passengers. Just five weeks after the first airmail flight, the first passenger arrived and Las Vegas became one of the first American cities with combination passenger and airmail service.

By the end of the decade, WAE reached as far as Dallas, Kansas City and Seattle, operating the longest network of any American airline. Sleeker and faster Boeing monoplanes soon replaced the sturdy M-2s for mail service, and spacious twelve-seat Fokker tri-motors provided more passenger comfort.

In 1930, Western Air Express's rise abruptly stopped when Postmaster General William Folger Brown forced it to merge with Transcontinental Air Transport. The resultant Transcontinental and Western Airlines, also known as TWA, took over most of Western's old routes and equipment. Western Air Express was able to maintain a separate corporate existence, but with only the Los Angeles-to-Salt Lake City and Cheyenne-to-Colorado Springs routes. The merger left Hanshue as president of TWA, as well as the old Western Air Express, with the latter holding forty-five percent of the stock. But TWA began losing money immediately. This threatened to take down what remained of Western Air Express along with TWA.

Western Air Express struggled for several years, at one point depending solely on the revenue from five slot machines it owned in the Las Vegas terminal for its profit. However, Western rebuilt its position as an industry leader, changing its name to Western Air Lines to reflect the change from total dependency on airmail to passenger travel. It served Las Vegas until April 1, 1987, when it merged with Delta.