Strabo, Geography

For the sea was raised by an earthquake and it submerged Helice, and also the temple of the Heliconian Poseidon, whom the Ionians¹ worship even to this day, offering there² the Pan-Ionian sacrifices. And, as some suppose, Homer recalls this sacrifice when he says: “"but he breathed out his spirit and bellowed, as when a dragged bull bellows round the altar of the Heliconian lord."
”³And they infer that the poet lived after the Ionian colonization, since he mentions the Pan-Ionian sacrifice, which the Ionians perform in honor of the Heliconian Poseidon in the country of the Prienians; for the Prienians themselves are also said to be from Helice; and indeed as king for this sacrifice they appoint a Prienian young man to superintend the sacred rites. But still more they base the supposition in question on what the poet says about the bull; for the lonians believe that they obtain omens in connection with this sacrifice only when the bull bellows while being sacrificed. But the opponents of the supposition apply the above-mentioned inferences concerning the bull and the sacrifice to Helice, on the ground that these were customary there and that the poet was merely comparing the rites that were celebrated there. Helice was submerged by the sea two years before the battle at Leuctra. And Eratosthenes says that he himself saw the place, and that the ferrymen say that there was a bronze Poseidon in the strait, standing erect, holding a hippo-campus in his hand, which was perilous for those who fished with nets. And Heracleides⁴ says that the submersion took place by night in his time, and, although the city was twelve stadia distant from the sea, this whole district together with the city was hidden from sight; and two thousand men who had been sent by the Achaeans were unable to recover the dead bodies; and they divided the territory of Helice among the neighbors; and the submersion was the result of the anger of Poseidon, for the lonians who had been driven out of Helice sent men to ask the inhabitants of Helice particularly for the statue of Poseidon, or, if not that, for the model of the temple; and when the inhabitants refused to give either, the Ionians sent word to the general council of the Achaeans; but although the assembly voted favorably, yet even so the inhabitants of Helice refused to obey; and the submersion resulted the following winter; but the Achaeans later gave the model of the temple to the lonians. Hesiod⁵ mentions still another Helice, in Thessaly.