Tros was a ruler of Troy. The city was named after him
Tros was a ruler of Troy and the son of Erichthonius by Astyoche (daughter of the river god Simoeis) or of Ilus I, from whom he inherited the throne. Tros was the father of three sons: Ilus, Assaracus, and Ganymedes. He gave his name to the city, also named Ilion for his son Ilus. Tros's wife was said to be Callirrhoe, daughter of the river god Scamander and Acallaris, the daughter of Eumedes.
When Zeus abducted Ganymedes, 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 of the gods, a position of great distinction.
It was from Tros that the Dardanians were called Trojans and the land named the Troad.