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 Greece ordered three new ironclads of the . "Hydra" was ordered from the "Ateliers et Chantiers de la Loire" shipyard in St. Nazaire, France during the premiership of Charilaos Trikoupis. The ship, named for the island of Hydra, was launched in 1889, and by 1892, she and her sister-ships "Spetsai" and "Psara" were delivered to the Greek fleet. The ship was long between perpendiculars and had a beam of and a mean draft of . She displaced as built. She was powered by a pair of steam engines of unknown type; they were rated at and provided a top speed