In classical Greece, Lerna (Greek: Λέρνη) was a region of springs and a former lake near the east coast of the Peloponnesus, south of Argos. Its site near the village Mili at the Argolic Gulf is most famous as the lair of the Lernaean Hydra, the chthonic many-headed water snake, a creature of great antiquity when 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:
Lerna was one of the entrances to the Underworld, and the ancient Lernaean Mysteries, sacred to Demeter, were celebrated there. Pausanias (2.37.1) says that the mysteries were initiated by Philammon, the twin "other" of Autolycus. At the Alcyonian Lake, entry to the netherworld could be achieved by a hero who dared, such as Dionysus, who, guided by Prosymnus, went that way in search of his mother Semele. For mortals the lake was perilous; Pausanias writes:
Lerna (Greek: Λέρνα) is a former municipality in Argolis, Peloponnese, Greece. Since the 2011 local government reform it is part of the municipality Argos-Mykines, of which it is a municipal unit. The seat of the municipality was Myloi. Population 3,042 (2001).
Lerna was a region in classical Greece.
Lerna may also refer to: