Torrey Pines is one of the most popular nature preserves in the city, and with good reason. More than 2,000 acres of natural land were set aside to provide San Diegans a respite from development. Running through the winding trails, it’s easy to get a sense of what California was like before all the freeways came along. Build your own run here, as there are many trails and distances, from half-mile to 5+ mile loops. Start at the beach and work your way up the bluff-side trails, or head up the super-steep paved road and take one of the many trails heading downward. There is free parking, but to save you the hassle of finding a spot that might not be where you want to start your run, there's a paid lot that costs anywhere between $10-$15, depending on the day and season.