Lower Potamus

Lower Potamus, Potamus Hypenerthen or Potamos Hypenerthen (Ancient Greek: Ποταμός ὑπένερθεν), was a deme of ancient Athens. It lay on the east coast north of Thoricus, and was once a populous place: it was celebrated as containing the sepulchre of Ion.[1][2][3][4]

Lower Potamus is tentatively located at Panepistemioupolis.[5][6]
References

Strabo. Geographica. ix. pp, 398, 399. Page numbers refer to those of Isaac Casaubon's edition.
Pausanias. Description of Greece. 1.31.2. , 7.1.2.
Pliny. Naturalis Historia. 4.7.11.
Suda, s.v. Ποταμός; Harpocr., s.v. Ποταμός
Lund University. Digital Atlas of the Roman Empire.
Richard Talbert, ed. (2000). Barrington Atlas of the Greek and Roman World. Princeton University Press. p. 59, and directory notes accompanying.