The topography of Neapolis along with the Odeon theatre occupies the northern part of the Forum, to the North of the Temple of Castor and Pollux now surmounted by the Church of San Paolo Maggiore, in modern blocks between via Anticaglia, via Sao Paulo and vico Giganti courts.
If the odeion few remains are known, the Roman Theatre is best known, remembered by ancient documents written and probably represented in works of art of the 15th and 16th centuries. The building, built in opus mixtum faced by reticulatum and, given latericium in appearance now visible between the late 1st and early 2nd century AD, when it was completely rebuilt, perhaps after the earthquake of 62 or the eruption of 79 ad. The Roman Theatre is not trace building for performances of the Greek or the early stages of the Roman age. The theatre was then abandoned in the middle of the 5th century a.d., when they changed the functions of the site; in some parts of the building were occupied by public burial nuclei, attributable to the 6th and 7th century AD, while others were obliterated by large accumulations of cultivable land. The archeological monument builds in fact a significant example of "urban archaeologists" through which it is possible to reconstruct the building history, from antiquity to the modern era, an entire urban area of Naples.
After some fortuitous discoveries occurred in 1859, which allowed him to draw a plan of the building, before the first excavations carried out between 1881 and 1891 led to the discovery of the Auditorium inside the garden of one of the blocks of flats overlooking the decumanus (the old way) top of the city. As a result, the investigations conducted with scientific methods allowed in 1985 accurately detect and isolate the wall structures of Roman times between modern and then, since 1997, to explore the area Meanwhile buy State property to the public. With the new systematic excavations were brought to light some of the ambulatory and outer core, with niches and a complex system of channeling water, with its support wedges and the vomitoria (access), leading to the bleachers of the cavea (the middle part) of the stands, as well as part of the scene with the intent to return the monument to public fruition as part of an overall program of enhancement of the entire urban area. Not less important are the decorated surfaces of floors survivors: ambulatory to internal plasters, some of them with interesting graffiti inscriptions, the coverings of the bleachers of the cavea. In subsequent speeches are expected to extend the investigation to also act as front (stage building) where took place the theatre, also celebrated in ancient sources.