Piraeus (/paɪˈriːəs, pɪˈreɪəs/ py-REE-əs, pirr-AY-əs; Greek: Περιφερειακή ενότητα Πειραιώς, romanized: Perifereiakí enótita Peiraiós), also sometimes called Greater Piraeus[2] (as distinct from the City of Piraeus; Ευρύτερος Πειραιάς Evrýteros Peiraiás), is one of the regional units of Greece.

It is part of the region of Attica.

The regional unit covers the west-central part of the Athens urban area (or agglomeration).

As a part of the 2011 Kallikratis government reform, the regional unit Piraeus was created out of part of the former Piraeus Prefecture.

This Attica location article is a stub.