Strap on your boots for this one: There's a reason this stretch of sand just beyond the Golden Gate is one of San Francisco's great unknowns. What was once the site of Adolph Sutro's private railroad, meant to lure daytrippers out to his Sutro Baths, is now nothing more than a narrow trail perched atop steep cliffs overlooking treacherous Pacific waves. Maneuver past Dead Man's Point, and the prize awaits you at the bottom of the 100-plus steps down a steep trail: nothing but a secluded, nearly deserted stretch of saltwater and sand ahead, and no reminder of the crowded bus you just stepped off. Sit and listen to the foghorns, and relax. Views of sun-drenched Marin are fine, but somehow the foggy days are the finest, when the wall of gray obscures everything but the few rocks offshore.