The ancient theatre at Delphi was built further up the hill from the Temple of Apollo giving spectators a view of the entire sanctuary and the valley below.  It was originally built in the 4th century BC but was remodeled on several occasions, particularly in 160/159 B.C. at the expenses of king Eumenes II of Pergamon and in 67 A.D. on the occasion of emperor Nero's visit.  The koilon (cavea) leans against the natural slope of the mountain whereas its eastern part overrides a little torrent which led the water of the fountain Cassotis right underneath the temple of Apollo. The orchestra was initially a full circle with a diameter measuring 7 meters. The rectangular scene building ended up in two arched openings, of which the foundations are preserved today. Access to the theatre was possible through the parodoi, i.e. the side corridors. On the support walls of the parodoi are engraved large numbers of manumission inscriptions recording fictitious sales of the slaves to the god. The koilon was divided horizontally in two zones via a corridor called diazoma. The lower zone had 27 rows of seats and the upper one only 8. Six radially arranged stairs divided the lower part of the koilon in seven tiers. The theatre could accommodate about 4,500 spectators. On the occasion of Nero's visit to Greece in 67 A.D. various alterations took place. The orchestra was paved and delimited by a parapet made of stone. The proscenium was replaced by a low pedestal, the pulpitum; its façade was decorated with scenes from Hercules' myth in relief. Further repairs and transformations took place in the 2nd century A.D. Pausanias mentions that these were carried out under the auspices of Herod Atticus. In antiquity, the theatre was used for the vocal and musical contests which formed part of the programme of the Pythian Games in the late Hellenistic and Roman period. The theatre was abandoned when the sanctuary declined in Late Antiquity. After its excavation and initial restoration it hosted theatrical performances during the Delphic Festivals organized by A. Sikelianos and his wife, Eva Palmer, in 1927 and in 1930. It has recently been restored again as the serious landslides posed a grave threat for its stability for decades

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