Phlius (; , Phleious) was a Greek city in the northwestern Argolid (now in modern Corinthia, near Nemea), in the Peloponnese, said to be named after the Greek hero Phlias but formerly called Araethyrea (; Ἀραιθυρέα, Araithurea).

Phlius (; , Phleious) was a Greek city in the northwestern Argolid (now in modern Corinthia, near Nemea), in the Peloponnese, said to be named after the Greek hero Phlias but formerly called Araethyrea (; Ἀραιθυρέα, Araithurea).