The "Mother Road" hauled it all, traversing the American West from Chicago to Santa Monica Beach, the last 350 miles through Southern California. For settlers, Depression-era "Okies" and "Arkies," and post-World War II families bound for suburbia, Route 66 was a migration funnel for generations. Wending through the mountains and badlands of San Bernardino County into Los Angeles County, Route 66 became a state of mind and a catchphrase for travelers everywhere, especially after singer Bobby Troupe popularized the hit song "(Get Your Kicks on) Route 66" and actors Martin Milner and George...