Hacıtuğrul, Afyonkarahisar, and Konya, which would have provided to the Lydian kingdom access to the produce and roads of Phrygia. The presence of a Lydian ivory plaque at Kerkenes Daǧ suggests that Alyattes's control of Phrygia might have extended to the east of the Halys River to include the city of Pteria, with the possibility that he may have rebuilt this city and placed a Phrygian ruler there: Pteria's strategic location would have been useful in protecting the Lydian Empire from attacks from the east, and its proximity to the Royal Road would have made of the city an important centre from which caravans could be protected. Phrygia under Lydian rule would continue to be administered by its local elites, such as the ruler of Midas City who held Phrygian royal titles such as (king) and (commander of the armies), but were under the authority of the Lydian kings of Sardis and had a Lydian diplomatic presence at their court, following the framework of the traditional vassalage treaties used since the period of the Hittite and Assyrian empires, and according to which the Lydian king imposed on the vassal rulers a "treaty of vassalage" which allowed the local Phrygian rulers to remain in power, in exchange of which the Phrygian vassals had the duty to provide military support and sometimes offer rich tribute to the Lydian kingdom. This situation continued under the rule of Croesus, with one inscription attesting of the presence of Croesus's son Atys at the court of one local ruler of Midas City himself named Midas. At Midas City, Atys held the position of priest of the sacred fire of the mother goddess Aryastin, and through him Croesus provided patronage to the building of the religious monument in the city now known as the Midas Monument. The presence of Atys at the court of this Midas might have inspired the legend recounted by Herodotus, according to which Croesus had a dream in which Atys was killed by an iron spear, after which he prevented his son from leading military activities, but Atys nevertheless found death while hunting a wild boar which was ravaging Lydia, during which he was accidentally hit by the spear thrown by the Phrygian prince Adrastus, who had previously exiled himself to Lydia after accidentally killing his own brother. Croesus also brought Caria, whose various city-states had since Gyges been allied to the Mermnad