Massive column drums and blocks are still conspicuous in the walls of the late antique fortress that guarded the Isthmus, and early travellers imagined that the temple and its precinct lay inside the walls. In the 1930s, the British archaeologist RJH Jenkins and his young architect, H. Megaw, set out to test the prevailing theory. Since they found only Roman remains beneath the fortress, they looked for the temple elsewhere in the vicinity but did not locate it.

The present excavations have their origins in discussions that took place during the Second World War at the Institute of Advanced Study in Princeton. It was home to a group of scholars exiled from their work in Greece. They included the Swedish-born, American archaeologist Oscar Broneer and Paul Clement. The exiles entertained themselves by discussing what archaeological tasks particularly needed to be performed in Greece after the war was over. There was agreement that the one major Panhellenic site that still needed exploration was the Sanctuary of Poseidon on the Corinthian Isthmus, the site of the Isthmian Games.

In 1946, Oscar Broneer returned to Greece to be acting director of the American School of Classical Studies in Athens, a post he held until he was appointed to a professorship of Classics at the University of Chicago in 1948. It was at the urging of the University of Chicago that he organised excavations on the Isthmus.

Swedish-born, American archaeologist Oscar Broneer conducted excavations on the site from 1954 to 1967

The project began in April of 1952. A survey of the topography led Broneer to conclude that the only possible site in which a large temple could have stood was a plateau at the foot of a small ridge, known locally as the Rachi (ÑÜ÷ç). It was there that he laid out a long and narrow trench to reveal whatever lay concealed beneath the surface. On the first day, the characteristic ground plan of a Doric temple emerged.

Broneer, however, did not, as he had expected, encounter the blocks of the foundations but simply the empty trenches where they had once lain. The temple had been almost completely destroyed, its blocks moved in late antiquity to construct the massive fortress, always visible, that was meant to guard against invasions from the north. Broneer was accompanied in that first season by a young Greek archaeologist, Chrysoula Kardara, who was later to become a professor at the University of Athens.

Early finds

Undeterred by the destruction of the temple, Broneer conducted excavations from 1954 to 1967. He systematically laid bare the central area of the sanctuary surrounding the temple, the stadium that lay adjacent to it and the theatre. He explored the later stadium of Hellenistic and Roman times, the Roman Bath, fortress and a small Hellenistic settlement located on the Rachi ridge above the sanctuary areas.

One significant discovery was the early Archaic temple lying beneath the Doric building of Classical times. A catastrophic fire reduced the building and its contents to a mass of smouldering ruins amongst which Broneer recovered a host of small dedications brought by pilgrims to Poseidon's shrine.

The remains of larger pieces, including bronze statues, were melted down and recast. The objects that remained, some of them small and exquisite, include a carnelian seal stone carved with the image of a young man, a tiny gold bull complete in every detail (although less than one centimetre long), a gold pin head showing a jeweller's skill, carnelian beads from a necklace, and carved bone pieces from a board game.

Small and finely decorated oil vessels (aryballoi) were favoured dedications. A man who had been victorious in the pentathlon gave a jumping weight suitably inscribed. Its early letter-forms provide the first evidence for the pentathlon as an event in the games. A wheel from a chariot was dedicated, presumably in gratitude for a victory won at the Isthmian Games. Then there were arms and armour, dedications made by those who had been victorious in war. Humbler forms of dedication were the small terracotta figurines of horses and riders and of bulls, the animal sacred to Poseidon. As god of the sea, he also received small replicas of ships for a safe voyage.

Small and finely decorated oil vessels (aryballoi) were favoured dedications.

The excavations revealed not only structures from Archaic and Classical Greece, but produced vivid evidence of the sanctuary's continued life into the Roman period. From Imperial times, there is the shrine to the hero and god, Melikertes-Palaimon. He was the object of a mystery cult.

Evidence of this is to be seen in the many oil lamps found in his precinct next to the temenos of Poseidon. They would have belonged to the initiates who took part in rites enacted in the darkness of night that included the sacrifice of a bull burned in a pit.

Later work

Broneer was joined in 1967 by his friend from his Princeton days, Paul Clement, now a professor at UCLA. The first excavation season consisted of a joint campaign in which Broneer finished his work in the sanctuary and Clement began clearing portions of the Late Roman fortifications that he called the Hexamilion.

From the roadway of the Northeast Gate came two marble stelae that had been used as paving stones. They had originally been erected in honour of victors in the Isthmian games of Roman times. One of them, preserved in its entirety, carries the portrait of Cornelius of Corinth, who had won first prize as a flute-player in games throughout the Roman Empire.

Clement then continued to conduct excavations that centred on the Roman Bath and structures in a field east of the main sanctuary. There emerged in the course of excavations in the bath a very large and complete black-and-white mosaic floor showing a Triton carrying a Nereid on his back with sea creatures swimming beside him.

Passing the torch

On Broneer's retirement in 1976, Elizabeth Gebhard followed him as director of the University of Chicago Excavations at Isthmia, and in 1987 Timothy Gregory took over Clement's work for the Ohio State University. The two projects continue; they concentrate on research, conservation and publications.

A major excavation took place in 1989 under the direction of Frederick Hemans and myself. Evidence was uncovered that revealed a much earlier beginning for Poseidon's cult in the Early Iron Age than had been previously imagined. Further exploration of the Archaic Temple revealed important information about its plan and date, while tests throughout the sanctuary produced vital information for securing the chronology of the site.

To explore the surrounding territory, Gregory and Daniel Pullen (of Florida State University) some years later conducted a systematic survey designed to place the Isthmian Sanctuary in its broader context. The survey has recovered details of life in the eastern Corinthia from the Neolithic period until today, and it has provided new information about activity on this "crossroads of Greece", including many new sites, several of which are now under intensive investigation.

The Isthmia Museum, which contains exhibits relating to the sanctuary and the nearby port of Kenchreai, opened in 1978. Now, 30 years later, renovations are underway under the aegis of the Greek Archaeological Service and the 37th Ephoreia of Prehistoric and Classical Antiquities. The site and museum will soon be opened again to the public.