Akanthos (Ancient Greek: Ἄκανθος; Latin: Acanthus), later Ierissos (Greek: Ιερισσός), was an ancient Greek city on the Athos peninsula. It was located on the north-east side of Akti, on the most eastern peninsula of Chalcidice. Strabo and Ptolemy erroneously place Acanthus on the Singitic Gulf, but there can be no doubt that the town was on the Strymonian Gulf, as is stated by Herodotus and other authorities: the error may have perhaps arisen from the territory of Acanthus having stretched as far as the Singitic Gulf.