Athens Metro Line 2 (Anthoupoli – Elliniko)

Opened 28 January 2000 with seven stations (Sepolia, Attiki, Larissa Station, Metaxourgeio, Omonia, Panepistimio, Syntagma). Greek Wikipedia dates the start of the original Athens Metro works, covering Lines 2 and 3, to November 1992, when the tunnel boring machines began excavating. No contract value for Line 2 alone was found, so none is recorded. Length measured from OpenStreetMap geometry.

Opened 15 November 2000 with five stations (Akropoli, Syngrou–Fix, Neos Kosmos, Agios Ioannis, Dafni). Length measured from OpenStreetMap geometry.

Opened 5 June 2004 with one new station, Agios Dimitrios. Length from the station table of Greek Wikipedia.

Opened 9 August 2004 with one new station, Agios Antonios. Length measured from OpenStreetMap geometry.

Opened 6 April 2013 with two new stations (Peristeri, Anthoupoli). Greek Wikipedia gives 5 April 2013, the date Attiko Metro handed the stations to STASY; its press release of that day says revenue service began "this Saturday", which is 6 April. Length measured from OpenStreetMap geometry.

Opened 26 July 2013 with four new stations (Ilioupoli, Alimos, Argyroupoli, Elliniko). Length is the sum of the station-to-station distances in the Greek Wikipedia table (1.25, 1.28, 1.7 and 1.15 km).