Halirrhotius

Halirrhotius (or Halirrhotios) was the son of Poseidon in Greek mythology.When Halirrhotius raped Alcippe, Ares' daughter by Aglaulus, Ares murdered him. Ares was tried in a court made up of his fellow gods, the first murder trial in history. The trial was held atop the Acropolis of Athens, on what became known as the Areopagus. Ares was acquitted.
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[Greek] A son of Poseidon. He pursued Alcippe, a daughter of Ares and Aglaulus, with his love, for which Ares killed him.