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 frigate Hydra delivered to the Hellenic Navy on 15 October 1992 and first sailed in Greek waters on 28 January 1993. The crest of the frigate "Hydra" is the same as that of her predecessor. It is based on one of the flags which the ships of Hydra sailed under during the 1821 revolution. In April 1988, the Hellenic Navy proposed and approved the four frigates of the MEKO 200 type in an effort to modernize its fleet. After a lengthy negotiation process, the following contracts were signed to fulfill the program: Greek frigate Hydra Hydra" (F-452) (Greek Φ/Γ "Ύδρα) is the