A.E.K., known as A.E.K., is a major Greek multi-sport club based in Nea Filadelfeia, Athens. The club is more commonly known in European competitions as A.E.K. Athens.

Nea Filadelfeia is a suburban town in the Athens agglomeration, Greece. Since the 2011 local government reform it is part of the municipality Nea Filadelfeia-Nea Chalkidona of Central Athens regional unit, of which it is the seat and a municipal unit. The municipal unit has an area of 2.850 km2. It was named after the Anatolian city Filadelfeia, now Alaşehir in Turkey, and it was settled by Greek refugees from Asia Minor after the Greco-Turkish War (1919-1922).