Naples is one of the oldest cities of the western world. Its historic city centre is the largest in Europe is listed as a UNESCO World Heritage Site.  Naples is also near the famous volcano Vesuvius and the ruins of the ancient Roman towns of Pompeii and Ercolano . Before italian unification it was the capital of Kingdom of the Two Sicilies and the most important and populated city of Italy. Naples is well known for cuisine , especially for pizza . In the city there are many tourist attractions, such as the Royal Palace , the basilica of Santa Chiara , the Gesù Nuovo (New Jesus) church, Castel dell'Ovo , the Castel Nuovo , the Castel Sant'Elmo , the city's Duomo , the Real Teatro di San Carlo (the oldest continuosuly active opera house in the world), the Palace of Capodimonte , the Naples underground geothermal tunnels , the Via Tribunali , Spaccanapoli street, the Veiled Christ (one of the world's most remarkable sculptures), the various catacombs around the city (for example the Catacombs of San Gennaro , or the Fontanelle cemetery , or the Catacombs of Saint Gaudiosus ), the Umberto I Gallery and the Via Toledo with its metro considered one of the most beautiful of Europe.    The Archaeological Museum of Naples is the most important in the world regarding Roman history, also include Egiptian and Greek finds. It is the home of the Federico II , the oldest public and secular university in the world, and of the L'Orientale , the oldest school of Sinology and Oriental Studies in Europe. Naples also boasts one of the most picturesque waterfront promenades, and charming locations at Gaiola Island and Marechiaro. Close to Naples there are a myriad of world-renowned tourist attractions such as the Amalfi Coast , Capri island, Ischia island, Procida island, the picturesque city of Sorrento , and the city of Salerno .