The Teatro di San Carlo was commissioned in 1737 by Charles VII of Bourbon, the young king of Naples and Sicily who would later reign as Charles III of Spain. The court needed a royal opera house worthy of a new dynasty and a capital that was, at the time, one of the largest cities in Europe; the older Teatro San Bartolomeo had become inadequate. The Sicilian nobleman and royal architect Giovanni Antonio de Medrano was charged with the design, while the impresario Angelo Carasale managed the construction and the staging. The cantiere was driven hard — roughly eight months from groundbreaking to opening night — and the theatre was inaugurated on 4 November 1737, the king’s name day, with Achille in Sciro by Domenico Sarro on a libretto by Pietro Metastasio. The San Carlo opened forty-one years before La Scala in Milan and almost half a century before La Fenice in Venice, and its horseshoe-shaped hall — the oldest of its kind — became a model for the great Italian opera houses of the following century.

On the evening of 13 February 1816, during the preparation of a ballet rehearsal, a fire broke out and destroyed the interior of the theatre, sparing only the perimeter walls. King Ferdinand IV entrusted the reconstruction to Antonio Niccolini, who had already worked on the building, and the impresario Domenico Barbaja drove the site at extraordinary speed: the rebuilt San Carlo reopened on 12 January 1817, ten months after the fire. Niccolini gave the theatre its present face — a neoclassical facade with a five-bay portico on Via San Carlo and a loggia above — and a redesigned auditorium with six tiers of boxes arranged in a horseshoe around the royal box, a deep proscenium and gilded decoration on a red and gold palette. The painted ceiling and the bas-reliefs of the proscenium frame the stage as a continuous court setting, and the capacity settled at 1,379 seats, with standing room raising the figure considerably higher in the 19th century.

Through the 19th and 20th centuries the San Carlo hosted the premieres of operas by Rossini, Donizetti and the young Verdi, and remained the principal stage of the Neapolitan school. Twentieth-century restoration campaigns repaired bomb damage from the Second World War and renewed the gilding, the stage machinery and the boxes; further conservation work followed in the early 2000s. The theatre lies within the UNESCO World Heritage Site of the Historic Centre of Naples, adjacent to the Royal Palace and the Galleria Umberto I. Today it operates as an active opera house and ballet theatre with a year-round season of around 120 performances, combining its own productions with international guest companies, and maintains a long institutional bond with the Conservatorio di San Pietro a Majella — making the Teatro di San Carlo, almost three centuries after its opening night, the oldest continuously operating opera house in the world.