Sumatia or Soumatia, or Sumetia or Soumetia (Σουμητία), also known as Sumateium or Soumateion (Σουμάτειον), or Sumeteia or Soumeteia (Σουμήτεια), was a town of ancient Arcadia in the district Maenalia, on the southern slope of Mount Maenalus. According to Greek mythology, Sumatia was founded by Sumateus, a son of Lycaon. Pausanias says that Sumatia was one of the towns in the territory of Maenalus, and was one of the towns that united to form Megalopolis.