California State Route 39, also known as the San Gabriel Canyon Road, is a scenic highway located in Los Angeles County. It stretches approximately 20 miles, connecting the city of Azusa to the Angeles National Forest. The route offers beautiful views of the surrounding mountains and is popular for outdoor activities like hiking and biking. The highway begins at the intersection with California State Route 210 and ends at the Crystal Lake Recreation Area. It serves as a vital access point for visitors looking to explore the natural beauty of the San Gabriel Mountains, making it a favored destination for both locals and tourists.