The city of Naples is built at the base and on the slopes of a range of volcanic hills, and, rising from the shore like a theatre, is seen to best advantage from the sea. From the summit occu pied by the castle of St. Elmo a transverse ridge runs south to form the promontory of Pizzofalcone, and divides the city into two natural crescents. The western crescent, known as the Chiaja ward, though merely a long narrow strip between the sea and Vomero hill, is the fashionable quarter most frequented by for eign residents and visitors. A fine broad street, the Riviera di Chiaja, was begun at the close of the 16th century by Count d'Olivares, and completed by the duke de Medina Celi (1695 1700), running for a mile and a half from east to west, ending in the quarter of Mergellina and Piedigrotta, at the foot of the hill of Posilipo. In front lie the public gardens of the Villa Nazionale, the chief promenade of the city, which were first laid out in 1780, and have been successively extended in 1807, in 1834, and again in recent years; and the whole edge of the bay from the Castel dell' Ovo to Mergellina is lined by a massive embankment and carriage-way, the Via Caracciolo, constructed in 1875-81. The eastern crescent includes by far the largest, as well as the oldest, portion of Naples.
The best known thoroughfare is the historic Toledo (officially Via Roma), which runs almost due north from the Piazza del Plebiscito in front of the Palazzo Reale, till, as Via Nuova di Capodimonte, crossing the Ponte della Sanita (constructed by Murat across the valley between Santa Teresa and Capodimonte), it reaches the gates of the Capodimonte palace, thus dividing the city into two parts. A fine street, the Corso Vittorio Em manuele, winds along the slopes behind the city from the Mer gellina railway station till it reaches the museum by the Via Sal vator Rosa. The character of the shore of the eastern crescent has been much altered by the new harbour works, which, with the wharves and warehouses, have absorbed the Villa del Popolo, or People's Park, originally constructed on land reclaimed from the bay. The two crescents have now been united by the con struction of a connecting thoroughfare on the seaward side of the Castel Nuovo, the royal palace, and the hill of Pizzofalcone ; while a tunnel (the Galleria della Vittoria) has been cut under this hill, thus further uniting the east and west halves of the city. There is also a metropolitan underground railway between the central station at Naples and Pozzuoli.
The streets of Naples are generally well-paved with large blocks of lava or volcanic basalt. In the older districts there is a count less variety of narrow gloomy streets, many of them steep. The houses are mostly five or six storeys high, are covered with stucco made of a kind of pozzolana, which hardens by exposure, and have large balconies and flat roofs. The castle of S. Elmo (S.
Erasmus), which dominates the whole city, had its origin in a fort (Belforte) erected by King Robert the Wise in 1329. The present building, with its rock-hewn fosses and massive ramparts, was constructed by Don Pedro de Toledo in 1537-46, and was long considered practically impregnable. It is now a military prison. On a small island (I. del Salvatore, the Megaris of Pliny), now joined to the shore at the foot of the Pizzofalcone by an arch-supported causeway, stands the Castel dell' Ovo, re stored in the 16th century. Castel Nuovo, a very picturesque building constructed near the harbour in 1279-82 by Charles I. of Anjou, contains between the round towers of its façade the tri umphal arch erected in to Alfonso I. In the interior is a fine Gothic hall. (See CELESTINE V.) The whole building has recently been restored. Castel del Carmine was demolished in 1906. The royal palace, begun in 1600 from designs by Domenico Fontana, partly burned in 1837, and repaired and enlarged by Ferdinand II., is an enormous building with a sea frontage of Boo ft. and a main façade 554 ft. long and 95 ft. high, exhibiting the Doric, Ionic and Composite orders in its three storeys. It now contains the important National Library (Biblioteca Na zionale Vittorio Emmanuele PT) with valuable books and mss., including mss. recovered from Austria after the war, which had been removed to Vienna by Charles V. Another royal palace, that of Capodimonte, contains a gallery of modern pictures and a fine collection of 18th century Neapolitan porcelain.
Naples has 237 churches and 57 chapels. Most of the churches are notable rather for rich internal decoration than for architectural beauty. The cathedral of St. Januarius was erected in 1294-1323. The general plan is that of a basilica with a nave and two (Gothic vaulted) aisles separated by pilasters. The western façade was completed in 1906. Beneath the high altar is a subterranean chapel containing the tomb of St. Januarius (San Gennaro), the patron saint of the city; in the right aisle there is a chapel (Cappella del Tesoro) built between 1608 and 1637 in popular recognition of his having saved Naples in 1527 "from famine, war, plague and the fire of Vesuvius"; and in a silver tabernacle behind the high altar of this chapel are pre served the two phials partially filled with his blood, the periodical liquefaction of which forms a prominent feature in the religious life of the city. Accessible by a door in the left aisle of the cathe dral is the church of Sta. Restituta, a basilica of the 4th century. Its baptistery contains important mosaics of that period. Santa Chiara (14th century, richly restored in the baroque style in the 18th) is interesting for a fresco ascribed to Giotto (at one time there were many more), and monuments to Robert the Wise, his son's wife, Mary of Valois, and his daughter Mary, empress of Constantinople.