Lerna Heracles killed it, as the second of his labors. The strong Karstic springs remained; the lake, diminished to a silt lagoon by the 19th century, has vanished. Lerna is notable for several archaeological sites, including an Early Bronze Age structure known as House of the Tiles, dating to the Early Helladic period II (2500–2300 BC). The secret of the Lernaean spring was the gift of Poseidon when he lay with the "blameless" daughter of Danaus, Amymone. The geographer Strabo attests that the Lernaean waters were considered healing: Lake Lerna, the scene of the story of the Hydra, lies in Argeia
Greek ironclad Hydra fleet, which included "Turgut Reis", "Barbaros Hayreddin", two outdated ironclad battleships, nine destroyers and six torpedo boats, sortied from the Dardanelles at 9:30. The smaller ships remained at the mouth of the straits while the battleships sailed north, remaining near to the coast. The Greek flotilla, which included the armored cruiser "Georgios Averof" and "Hydra" and her sisters, had been sailing from the island of Imbros to the patrol line outside the straits. When the Ottomans were sighted, the Greeks altered course to the northeast, in order to block the advance of their opponents. In the ensuing Naval Battle of