Alpheus
ALPHEUS ('Alfeios; mod. Ruphia), the chief river of Peloponnesus. Strictly Ruphia is the modern name for the ancient Ladon, a tributary which rises in N.E. Elis, but the name has been given to the whole river. The Alpheus proper rises near Asea; but its passage thither by subterranean channels from the Tegean plain and its union with the Eurotas are probably mythical (see W. Loring, in Journ. Hell. Studies, xv. p. 67). It consists for the most part of a shallow and rapid stream, occupying but a small part of its broad, stony bed. It empties itself into the Ionian sea. Pliny states that in ancient times it was navigable for six Roman miles from its mouth. Alpheus was recognized in cult and myth as the chief or typical river-god in the Peloponnesus, as was Acholous in northern Greece. His waters were said to pass beneath the sea and rise again in the fountain Arethusa at Syracuse; such is the earlier version from which later mythologists and poets evolved the familiar myth of the loves of Alpheus and Arethusa.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)