The Celadon is a mythological river of Arcadia crossed by Heracles in pursuit of the Hind of Ceryneia, according to Pindar: it is mentioned by Strabo. Pausanias names it the Celadus and states that it is a tributary of the Alpheus.
In Homer's Iliad it is described as being under the walls of Pheia, not far from the river Iardanus, on the borders of Pylos: Ereuthalion was killed by Nestor here.
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Celadon (river) Wikipedia(Text) CC BY-SA