Book excerpt: The geography of Southern California is as infinitely varied as its population. From the serenity of coastal beaches to the majestic San Gabriel Mountains and the tight canyons of the Santa Monica Mountains, Los Angeles is a cyclist's paradise. The vistas are spectacular, the terrain fun to ride and the sights include some of Hollywood's best-known landmarks. Bicycling Los Angeles County takes riders on 40 different rides throughout Southern California's most popular destination. Also detailed for avid roadies are some of Los Angeles' most popular group rides - for those who want a more challenging and social outing.