Hyllus/Hyllos is also the name of a son of Herakles, see Hyllus.
Hyllus or Hyllos (Greek: Ὕλλος) was the ancient name of a river of Asia Minor. It is a tributary of the river Hermus, in Lydia, flowing into Hermus from the north.[1] In the time of Strabo, the river was called Phrygius.[2]