Granada's — and perhaps Europe's — love letter to Moorish culture. Part palace, part fort, part World Heritage site, the Alhambra has long enchanted a never-ending line of expectant visitors. The Palacios Nazaríes with its astonishing muqarnas ceilings, the Patio de los Leones with its 12 marble lions, and the Generalife gardens are the pinnacle of Islamic art in Europe. Book tickets weeks in advance — 6000 visitors tramp through daily.