Kyzikos is a figure from Greek mythology, known as the king of the city of Kyzikos, located in the region of Mysia. He is often associated with the Argonauts' quest for the Golden Fleece. Kyzikos welcomed the Argonauts when they arrived in his city, offering them hospitality and assistance. Tragically, Kyzikos met his end due to a misunderstanding. After the Argonauts departed, they returned to Kyzikos' territory during the night, and in the confusion, Kyzikos mistook them for enemies. He was killed in battle, leading to a tragic turn of events for both him and the Argonauts, who mourned his loss.