For several weeks in both the spring and fall, make a detour off the trails at the Desert Botanical Garden and find yourself surrounded by butterflies. In fall, the assortment is rather limited, but still stunning, as you'll hang with black and orange monarchs. Spring brings more color. Either way, the humid, airy Marshall Butterfly Pavilion is paradise for both people and butterflies. When you leave, a garden volunteer will check you for hitchhikers.