Screw Magic Mountain. The best roller coaster in Southern California is the Mulholland Highway. It's an east-west route running through the Southern Transverse Ranges between U.S. Route 101 and the Pacific Coast Highway (aka PCH or State Route 1). It's the westernmost extension of California's famous Mulholland Drive in Hollywood, but the highway starts officially in Calabasas and goes west to PCH from there. Between it and Potrero Road, you can ride the full length of the Transverse Ranges from Camarillo to Hollywood without relying on PCH, which gets gridlocked at times (especially weekends). Mulholland Highway winds through chaparral country in and around Malibu territory, where all kinds of celebrities make their palace-sized homes. At the same time, though, there's plenty of country riding to be had here.
Starting out near the 101 and heading west, you'll find yourself amid a good number of fun curves in this hill country. Between the banked turns, diminishing curves with blind apexes, arcing rises, hill climbs and plunging chutes, there's plenty to test the mettle of any rider at any skill level. Once you pass Cornell, it gets a little more technical, with tons of esses and switchbacks. West of Cornell, you'll come across the Rock Store, the most famous rider hangout in all of South Cali. Jay Leno and other celebrity riders hang out there from time to time, and the place has pretty good grub. West of the Rock is where the roller-coaster ride really kicks into high gear. And low gear, and all the others, too. It's a technical course akin to driving through an intestine minus the smell of that tri-tip sammich you ate three days ago. If you really want to test your riding skills and have a vendetta against the finish on your floorboards, this is the place for you.
West of Kanan Road, you can either take the fork left onto Encinal Canyon Road or go right along Mulholland Highway. This segment's a little dangerous; there are some surprise turns that may require a lot of downshifting depending on how fast you're going. Riding past Decker Canyon Road, you're almost at the end of Mulholland. It's a downhill run to the Pacific Coast Highway from here to Leo Carillo State Beach. This marks the west end of Mulholland Highway, where it terminates at PCH. You can camp at some of the beaches also. From here you can head northwest along the coast all the way up to Northern California or cut southeast back to Santa Monica, where the highway becomes the beginning of Interstate 10 (the Pacific Coast Highway picks up again south of Redondo Beach, but that's another story).
If you want something a little more laid back than the west part of Mulholland Highway, there are alternate routes to PCH. Go a little west, and you'll hit Kanan Dume Road, which goes back to the coast. Head back east from the Rock Store, and you come across a number of canyon roads winding down through the hills to the Pacific Coast Highway or Los Angeles proper, such as Las Virgenes Road, Cold Canyon Road and Topanga Canyon Boulevard.
Either way, Mulholland Highway is a fun challenge. It's the Thanksgiving turkey of canyon carving, and as such, it gets plenty of action on the weekends, from riders of all kinds to cage jockeys. We went on a Friday afternoon, and traffic was fairly light. Weekdays are definitely the best time to go if you don't want to share the road with everybody.
Intersection of Topanga Canyon Boulevard and Mulholland Drive GPS: Lat 34.2995N, Long 118.6195W
Leo Carillo State Beach PS: Lat 34.06099N, Long 118.9265W
The Rock Store
Ed and Veronica ("Vern") came across a building in Southern California made entirely of volcanic rock. It had been a stagecoach stop in 1910, and they bought the place, turning it into a small town grocery store in 1961. The years brought a lot of change, especially as major roads were built connecting the Mulholland Highway to PCH. Locals took weekend drives up this way, and many of them rode bikes. More and more stopped by this little pit stop. Eventually it turned into a diner offering great breakfasts, sandwiches and a cold drink on a hot day.