The Department of Line 4 of the Athens Metro, “Veikos Goudi’s Alsos”, part of which is planned to be implemented with this project, has been designed to serve many densely populated areas of the Athens Basin with the construction of 4 new stations (Exarche, Kolonaki, Annunciation), decongestion of existing central stations Metro from the ever increasing demand of the passenger audience, with the construction of 4 new stations (Exarche, Accompany, Kolonaki, Evangelismos), the deconge of existing central stations of Metro from the ever increasing demand of the passenger audience, as well as the service of many important buildings and facilities. It has a length of about 12.9 km and includes: 15 new stations with their ventilation wells, 9 intermediate and/or terminal wells, Underground tunnels with TBM dual-track machinery, 12,1 km, underground tunnels with conventional mechanical means, double and triple track tunnels, 1 new Operational Control (KEL) and 1 backup, 12 new building of the maintenance and repair of the new trains, the required rolling stock, and the requisite treasury.