The golden-sand beach of Playa Tambor, fringed with coconut palms and sea grapes, makes for a postcard-perfect afternoon of horseback riding along the waterfront of Costa Rica’s Nicoya Peninsula. Even novice riders will find a horse that suits them, and guides will either keep the steeds at a “whoa, Nelly” pace or a let-it-rip gallop, depending on guests’ preferences.