Naples' wealth of cultural assets is extraordinary. You'll find two royal palaces, three castles, and ancient ruins that include some of Christianity's oldest frescoes. The city's Museo Archeologico Nazionale claims the world's finest collection of Pompeiian frescoes and mosaics, while its Cappella Sansevero holds Italy's most extraordinary marble sculpture. You'll find Caravaggio masterpieces in the Pio Monte della Misericordia, Palazzo Zevallos Stigliano and Museo di Capodimonte, the latter palace home to countless masterpieces. Of course, we could also mention all those frescoed baroque cupolas, but that would just be boasting.