|Regional unit||East Attica|
|o Municipal unit||8.136 km2 (3.141 sq mi)|
|Elevation||350 m (1,150 ft)|
|o Municipal unit||10,015|
|o Municipal unit density||1,200/km2 (3,200/sq mi)|
|Time zone||UTC+2 (EET)|
|o Summer (DST)||UTC+3 (EEST)|
Agios Stefanos (Greek: , meaning Saint Stephen) is a suburb in Athens, Greece. Since the 2011 local government reform it is part of the municipality Dionysos, of which it is the seat and a municipal unit. The municipal unit has an area of 8.136 km2.
Agios Stefanos is situated in the hills in the northeastern part of the Athens conurbation, at about 350 m elevation. It lies east of the Parnitha mountains, northwest of the Penteliko Mountain, and 4 km southwest of the Marathon Reservoir. The source of the river Kifisos is near Agios Stefanos. It is 9 km west of Marathon and 21 km northeast of Athens city centre. Its built-up area is continuous with those of the neighbouring suburbs Anoixi and Stamata to the south.
Motorway 1 (Athens - Lamia - Thessaloniki) passes west of the town. Agios Stefanos has a railway station on the railway from Athens to Thessaloniki. Athens ERA-1 transmitter, the second tallest man-made structure of Greece, is situated north of Agios Stefanos.
|Year||Town population||Municipality population|