The triangular forum
The Triangular forum derives its name from its geometric shape. It is located on the volcanic ridge overlooking on its south the Pompeian countryside. The entrance was from Via dei Teatri, where a vestibule with six Ionic columns formed its monumental façade. It was built in the second century B.C. like the civil Forum. The inner colonnade has 95 Doric columns and surrounds the area of an archaic Doric temple with limestone columns. The temple was first consecrated to Hercules alone and then also to Minerva.
It collapsed, probably in the II century B.C., because of the corrosion of the southern slant of Pompeii. The ruins of the temple and the sacred source - to which an heroon was also added subsequently in Sillana period, - were encircled in sannitic period with a tufa portico, that was used for sporting and recreational activities. In the III century B.C. it was built, close to the Triangular forum, in the hollow of the slant, a first Greek theater and, in Sillana period, another one that was covered. The Theater was completely reconstructed in the II century B.C. in tufa style. On the side of this theater there was a big tufa portico that served as a foyer for the spectators.
After 62 A.D. earthquake, the theater's peristyle was transformed in a school of gladiators, with a field for exercises. In Samnnite age there were also a gymnasium, a sacello of Isis and a small Temple of Zeus. After 62 A.D. the gymnasium was reduced to advantage the reconstruction of the Temple of Isis.