In Greek mythology, King Tros of Dardania (1375 BC - 1328 BC), son of Erichthonius from whom he inherited the throne and the father of three named sons: Ilus, Assaracus, and Ganymede. He is the eponym of Troy, also named Ilion for his son Ilus.
When Zeus abducted Ganymede, Tros grieved for his son. Sympathetic, Zeus sent Hermes with two horses so swift they could run over water. Hermes also assured Tros that Ganymede was immortal and would be the cupbearer for the gods, a position of much distinction.
In variant versions Ganymede is son of Laomedon son of Ilus son of Tros.
It was from Tros that the Dardanians were called Trojans and the land named the Troad.
...and Erichthonius succeeded to the kingdom and marrying Astyoche, daughter of Simoeis, begat Tros. On succeeding to the kingdom, Tros called the country Troy after himself, and marrying Callirrhoe, daughter of Scamander, he begat a daughter Cleopatra, and sons, Ilus, Assaracus, and Ganymede
Beside the Pelopium is a pillar of no great height with a small image of Zeus on it; one hand is outstretched. Opposite this are other offerings in a row, and likewise images of Zeus and Ganymedes. Homer's poem tells how Ganymedes was carried off by the gods to be wine-bearer to Zeus, and how horses were given to Tros in exchange for him. This offering was dedicated by the Thessalian Gnathis and made by Aristocles, pupil and son of Cleoetas.