DESCRIPTION
Athens metro network is constituted by 3 lines; the first one (Line 1) derives from the former Piraeus-Athens railway (end of XIX century), which was transformed during the time in a properly said metro (beginning of metro operations: 1957).
Line 2 runs north-west/south-east; its first phase opened in 2000 (Sepolia-Syntagma), with further extensions to Dafni-Aghios Dimitros (2000-2004); other extensions were completed in 2013: south-east to the elder airport at Helleniki, and north-west from Aghios Antonios to Anthoupoli. Line 2 interchanges with ground level railways at Larissa Station and with metro Line 1 at Omonia and Attiki.
Line 3 opened in 2003 (Ethniki Amyna-Syntagma on January and Syntagma- Monastiraki on April), after years of problematic works; difficulties were caused by archaeological and architectonic existing elements along the route, and by the particular characteristics of the soils. After a strong debate the choice was to utilize small TBMs instead of a bigger one after a soil consolidation. Line 3 was extended in 2004 (Ethniki Amyna-Doukissis Plakentias), 2007 (Monastiraki-Egaleo) and 2013 (Egaleo-Aghia Marina). Starting from July 2014 some of the Line 3 metro cars invert their voltage (from 750 V DC to 25 KV AC) at Doukissis Plakentias stop in order to prosecute up to Eleftherios Venizelos Airport along an existing railway track. Line 3 interchanges with Line 1 at Monastiraki and with Line 2 at Syntagma (2 levels station).