Helike (//; Greek: Ἑλίκη, pronounced [heˈlikɛː], modern Greek pronunciation: [eˈliki]) was an ancient Greek city that disappeared at night in the winter of 373 BC. It was located in Achaea, northern Peloponnesos, two kilometres (12 stadia) from the Corinthian Gulf and near the city of Boura, which, like Helike, was a member of the Achaean League. The city was thought to be legend until 2001, when it was rediscovered in the Helike delta. Modern research attributes the catastrophe to an earthquake and accompanying tsunami which destroyed and submerged the city.
Research efforts 
The submerged town was long one of the biggest targets for underwater archaeology. Scientists were divided in their opinions about the exact location of Helike. Numerous archaeologists, historians, professors and explorers wrote, studied and actively searched, trying to discover any trace of the ancient town, with little success. But their work, essays, observations and studies contributed to an important and growing body of knowledge. Among them are the following:
In 1826, François Pouqueville, French diplomat and archaeologist, who wrote the Voyage en Grèce; in 1851 Ernst Curtius the German archaeologist and historian who speculated about its location; in 1879 Julius Schmidt, the director of Athens Observatory, issuing a study comparing the Aegeion earthquake which occurred 26 December 1861 with an earthquake which might have destroyed Helike; in 1883 Spiros Panagiotopoulos, the mayor of Aegeion city, wrote about the ancient city; in 1912 the Greek writer P. K. Ksinopoulos wrote The City of Aegeion Through the Centuries, and in 1939 Stanley Casson, an English art scholar and army officer who studied classical archaeology and served in Greece as liaison officer, addressed the problem.
Other investigators include in 1948 the German archaeologist G. Karo; in 1950 Professor Robert Demangel, who was from 1933 to 1948 the director of the French School of Archaeology in Athens; in 1950 Alfred Philippson, German geologist and geographer; in 1952 Spiros Dontas, Greek writer and member of the Academy of Athens; in 1954 Aristos Stauropoulos, a Greek writer who published the History of the city of Aegeion; in 1956 the Greek Professor N. P. Moutsopoulos; in 1967 Spiros Marinatos, a Greek archaeologist who wrote the Research about Helike and in 1968 Helike-Thira-Thieves; in 1962 George K. Georgalas, the Greek writer; and in 1967 Nikos Papahatzis, a Greek archaeologist who published Pausanias’ Description of Greece.
In 1967, Dr. Harold Eugene Edgerton worked with the American researcher Peter Throckmorton. They were convinced that Helike was to be found on the seabed of the Gulf of Corinth. Dr. Edgerton perfected special sonar equipment for this research but permission to search was not granted by the Greek authorities. In 1967 and in 1976, Captain Jacques Yves Cousteau made some efforts with no result. In 1979 in the Corinthian Gulf, the Greek undersea explorer Alexis Papadopoulos discovered a sunken town and recorded his findings in a documentary film which shows walls, fallen roofs, roof tiles, streets, etc. at a depth of between 25 and 45 m. "Whether or not this town can be identified with Helike is a question to be answered by extensive underwater research. In any case, the discovery of this town can be regarded as an extremely interesting find", according to the journal Archaeology.
Dora Katsonopoulou, president of the Helike Society, and Steven Soter of the American Museum of Natural History rediscovered the city in the summer of 2001 near the village of Rizomylos. The World Monuments Fund included Helike in its 2004 and 2006 List of 100 Most Endangered Sites in an effort to protect the site from destruction.
Helike was founded in the Bronze Age, becoming the principal city of Achaea. The poet Homer states that the city of Eliki participated in the Trojan War with one ship. Later, following its fall to the Achaeans, Eliki led the Achaean League, an association that joined twelve neighboring cities in an area including today's town of Aigion. Eliki, also known as Dodekapolis (from the Greek words dodeka meaning twelve and polis meaning city), became a cultural and religious center with its own coinage. Finds from ancient Eliki are limited to two 5th century copper coins, now housed in the Staatliches Museum, Berlin. The obverse shows the head of Poseidon, the city's patron, and the reverse his trident. There was a temple dedicated to the Helikonian Poseidon.
Helike founded colonies including Priene in Asia Minor and Sybaris in South Italy. Its panhellenic temple and sanctuary of Helikonian Poseidon were known throughout the Classical world, and second only in religious importance to Delphi.
The city was destroyed in 373 BC, two years before the Battle of Leuctra, during a winter night. Several events were construed in retrospect as having warned of the disaster: some "immense columns of flame" appeared, and five days previously, all animals and vermin fled the city, going toward Keryneia. The city and a space of 12 stadia below it sank into the earth and were covered over by the sea. All the inhabitants perished without a trace, and the city was obscured from view except for a few building fragments projecting from the sea. Ten Spartan ships anchored in the harbour were dragged down with it. An attempt involving 2000 men to recover bodies was unsuccessful. Aegium took possession of its territory.
The catastrophe was attributed to the vengeance of Poseidon, whose wrath was excited because the inhabitants of Helike had refused to give their statue of Poseidon to the Ionian colonists in Asia, or even to supply them with a model. According to some authorities, the inhabitants of Helike and Bura had even murdered the Ionian deputies.
About 150 years after the disaster, the philosopher Eratosthenes visited the site and reported that a standing bronze statue of Poseidon was submerged in a "poros", "holding in one hand a hippocamp", where it posed a hazard to those who fished with nets.
Around AD 174 the traveler Pausanias visited a coastal site still called Helike, located 7 km southeast of Aigion, and reported that the walls of the ancient city were still visible under water, "but not so plainly now as they were once, because they are corroded by the salt water".
For centuries after, its submerged ruins could still be seen. Roman tourists frequently sailed over the site, admiring the city's statuary. Later the site silted over and the location was lost to memory.
Near the Gulf of Corinth, the ancient city of Helike fits the Atlantis profile as it was a flourishing city struck down in its prime by an earthquake in 373 BC. The city state was the centre of a cult of Poseidon, second only in importance to the Oracle at Delphi. Generations of fishermen in the Gulf have told of snagging their nets on statues of an apparently wrathful Poseidon. BBC Horizon claimed to have located the site.
Scholars who visited the ruins 
- The Greek geographer Strabo
- The Greek traveler Pausanias
- The Greek historian Diodoros of Sicily
- The Roman writer Aelian
- The Roman poet Ovid
Subsequent events 
On 23 August 1817, a similar disaster, an earthquake followed by a tsunami, occurred on the same spot. The earthquake was preceded by a sudden explosion, like that produced by a battery of cannon. The aftershock was said to have lasted a minute and a half, during which the sea rose at the mouth of the Selinous River and extended to cover all the ground immediately below Vostitza (the ancient Aegium). After its retreat, not a trace was left of some artillery depots which had stood on the shore, and the beach was carried away completely. In Vostitza 65 people lost their lives and two thirds of its buildings were entirely ruined, as were five villages in the plain.
Spyridon Marinatos, emphasizing the importance of the discovery of Helike, said that only the declaration of a third world war would obscure the discovery of Helike. He pointed out Helike as an unresolved problem of Greek archaeology in 1960. In 1988, the Greek archaeologist Dora Katsonopoulou launched the Helike Project to locate the site of the lost city. In 1994, in collaboration with the University of Patras, a magnetometer survey carried out in the midplain of the delta revealed the outlines of a buried building. In 1995 this target (now known as the Klonis site) was excavated and a large Roman building with standing walls was brought to light. The city was rediscovered in 2001 buried in an ancient lagoon. Since then, excavations have been carried out in the Helike delta each summer. Continuing excavations have brought to light significant archeological finds dating from prehistoric times when Helike was founded up until its revival in Hellenistic and Roman times.
See also 
- Ξινόπουλος, Π. Κ. (1912). Το Αίγιο διά μέσου των αιώνων.
- Σταυρόπουλος, Αρίστος (1954). Ιστορία πόλεως Αιγίου.
- Μαρινάτος, Σπύρος (1967). Έρευνα περί την Ελίκην Π.Α.Α. τ 41.
- Μαρινάτος, Σπύρος (1968). Ελίκη-Θήρα-Θήβαι Α.Α.Α. τ 1.
- Παπαχατζής, Νίκος (1967). Παυσανίου Ελλάδος Περιήγησις Αχαϊκά-Αρκαδικά.
- "Helike, the film of the discovery" 1979
- "Archaeology magazine, issue No 9, November 1983"
- Katsonopoulou, Dora (2002). "Helike and her Territory in Historical Times". Pallas 58: 175–182. ISSN 0031-0387.
- Lafond, Yves (1998). "Die Katastrophe von 373 v. Chr. und das Versinken der Stadt Helike in Achaia". In Olshausen, E.; Sonnabend, H. Naturkatastrophen in der antiken Welt. Stuttgarter Kolloquium zur historischen Geographie des Altertums (in German) 6. Stuttgart: Steiner. pp. 118–123. ISBN 3-515-07252-7.
- Giovannini, A. (1985). "Peut-on démythifier l'Atlantide?". Museum Helveticum (in French) 42: 151–156. ISSN 0027-4054.
- "Architect's mission in Cyprus: One man's quest to find Atlantis" The Independent, 24 August 2005
- Soter, Steven; Katsonopoulou, Dora (1999). "Occupation horizons found in the search for the ancient Greek city of Helike". Geoarchaeoology 14 (6): 531–563. doi:10.1002/(SICI)1520-6548(199908)14:6<531::AID-GEA4>3.0.CO;2-X.
- Katsonopoulou, Dora (2002). "Helike and her territory in the light of new discoveries". In Greco, E. Gli Achei e l'identità etnica degli Achei d'Occidente. Tekmeria 3. Paestum: Pandemos. pp. 205–216. ISBN 88-87744-03-3.
- Alvarez-Zarikian, Carlos A.; Soter, Steven; Katsonopoulou, Dora (2008). "Recurrent Submergence and Uplift in the Area of Ancient Helike, Gulf of Corinth, Greece: Microfaunal and Archaeological Evidence". Journal of Coastal Research 24 (1): 110–125. doi:10.2112/05-0454.1.
- Soter, Steven; Katsonopoulou, Dora (2011). "Submergence and uplift of settlements in the area of Helike, Greece, from the Early Bronze Age to late antiquity. Geology 26, 584-610.
- Marinatos, Spyridon N. (1960). "Helike. A submerged town of classical Greece". Archaeology 13: 186–193. ISSN 0003-8113.
- Alexis Papadopoulos, Discovering a sunken city Archaeology magazine, issue No 9, November 1983
- pdf Archaeology magazine, issue No 9, November 1983
- Helike, the film of the discovery
- Staatlichen museen The one and only coin of Helike
- Official Website of Helike Project
- BBC Science on the discovery of Helike
- 2004 World Monuments Watch List of 100 Most Endangered Sites
- Strabo, on Helike
- Discoveries at ancient Helike, Dora Katsonopoulou and Steven Soter, Jan. 2005