HAGNO was the Naiad Nymph of a spring on Mount Lykaios (Lycaeus) in Arkadia (southern Greece). She was one of three Arkadian wet-nurses of the god Zeus, the other two being the Nymphai Neda and Theisoa.
Like Neda she was probably one of the Okeanides.
HAGNO (Hagnô) an Arcadian nymph, who is said to have brought up Zeus. On Mount Lycaeus in Arcadia there was a well sacred to and named after her. When the country was suffering from drought, the priest of Zeus Lycaeus, after having offered up prayers and sacrifices, touched the surface of the well with the branch of an oak tree, whereupon clouds were formed immediately which refreshed the country with rain. The nymph Hagno was represented at Megalopolis carrying in one hand a pitcher and in the other a patera. (Paus. viii. 38, § 3, 31. § 2, 47. § 2.)
Source: Dictionary of Greek and Roman Biography and Mythology.
Pausanias, Description of Greece 8. 38. 2 (trans. Jones) (Greek travelogue C2nd A.D.) :
"There is a place on Mount Lykaios (Lycaeus) called Kretea (Cretea) [in Arkadia] . . . The Arkadians claim that the Krete (Crete), where the Kretan story has it that Zeus was reared, was this place and not the island. The Nymphai, by whom they say that Zeus was reared, they call Theisoa, Neda and Hagno. After Theisoa was named a city in Parrhasia; Theisoa today is a village in the district of Megalopolis. From Neda the river Neda takes its name; from Hagno a spring on Mount Lykaios, which like the Danube flows with an equal volume of water in winter just as in the season of summer. Should a drought persist for a long time, and the seeds in the earth and the trees wither, then the priest of Lykaios Zeus, after praying towards the water and making the usual sacrifices, lowers an oak branch to the surface of the spring, not letting it sink deep. When the water has been stirred up there rises a vapour, like mist; after a time the mist becomes cloud, gathers to itself other clouds, and makes rain fall on the land of the Arkadians."
Pausanias, Description of Greece 8. 41. 1 :
"A river called the Lymax flowing just beside Phigalia falls into the Neda, and the river, they say, got its name from the cleaning of Rhea. For when she had given birth to Zeus, the Nymphai who cleansed her after her travail threw the refuse into this river. Now the ancients called refuse [afterbirth] lymata."
Pausanias, Description of Greece 8. 31. 4 :
"[At Megalopolis in the enclosure of Demeter and Persephone:] The table also has a representation of Nymphai, Neda carrying the infant Zeus and another Arkadian Nymphe Anthrakia holding a torch, and Hagno with a water-jar in one hand and a drinking cup in the other; Ankhiroe and Myrtoessa are carrying water-jars and in fact water is pouring down from them."
Pausanias, Description of Greece 8. 47. 3 :
"Represented on the altar [of Athene at Tegea, Arkadia] are Rhea and the nymphe Oinoe holding the baby Zeus. On either side are four figures: on one, Glauke, Neda, Theisoa and Anthrakia; on the other Ide, Hagno, Alkinoe and Phrixa."
- Pausanias, Guide to Greece - Greek Geography C2nd AD