The tunnels of Metro Line 4 are being constructed at a rapid pace, and according to responsible government officials, among all the planned extensions, priority is being given to the one toward Glyfada in order to connect the network with the major urban redevelopment at Ellinikon. In fact, the extension toward Glyfada will have two branches.

One branch will head toward Upper Glyfada and another toward the city center via the Ellinikon area. With this addition, the Metro will, for the first time, have two branches on the same line.

In detail:

The tunnel boring machine (TBM) “Niki” began its route from the Alsos Veikou TBM shaft and has currently passed the ELIKONOS Station, approaching the next station, KYPSÍLI, having already constructed approximately 2,600 meters of finished tunnel.

After the KYPSÍLI station and once the necessary maintenance work has been carried out, it is expected to continue toward the DIKASTIRIA (Courts) Station.

It will then proceed toward the stations Alexandras, Exarchia, Akadimias, and Kolonaki.

According to the current schedule, its route is expected to be completed by the end of 2026, exiting via the special Evangelismos shaft located in the area of the Evangelismos Station.

The second TBM, “Athena,” began its route from the Katechaki TBM shaft and has currently passed the KAISARIANI Station, having constructed approximately 4,500 meters of finished tunnel. It is heading toward the new EVANGELISMOS Station, with its route expected to be completed in early 2026, also exiting via the special Evangelismos shaft.

To save time, the TBMs pass through future stations before they are excavated, and the same is planned for subsequent stations.

At the Panepistimioupoli station, an archaeological rescue excavation is underway (an ancient road has been found). At the Goudi station, archaeological excavations have been completed, but a main EYDAP water pipeline was discovered and the optimal solution is under review. At the Evangelismos station, there is the well-known legal appeal concerning Rizari Park, to which the opposition of the Municipality of Athens has also been added.

At the stations Alsos Veikou, Galatsi, Elikonos, Kypseli, Dikastiria, Alexandras, Akademia, Kolonaki, Zografou, Kaisariani, and Ilisia, station construction works are underway, while the Exarchia and Zografou stations were recently handed over to the construction consortium.

According to the current schedule, unless unforeseen construction difficulties arise, project completion under the contractual obligation is set for the end of 2029.

Extension of Metro Line 2 toward Ilion

The extension currently being implemented in Attica is that of Line 2 toward Ilion, approximately 4 km in length with three stations (Palatianí, Ilion, and Agios Nikolaos). At the same time, the project also includes the extension and modernization of the Eleonas depot, as well as the upgrade/replacement of the existing electromechanical (E/M) systems of Metro Lines 2 and 3. The first stage of the tender has been completed, and the second stage will follow shortly. Construction is estimated to begin in 2027, with a contractual delivery time of five years.

The Ilion extension project also includes the expansion of the existing Eleonas depot. Given that the future operation of the extension, as well as other current needs of HELLENIC METRO S.A., make it necessary to find and construct additional depot space, the expansion of the Eleonas depot into a neighboring adjacent area of approximately 20 stremmas (about 20,000 m²) will proceed simultaneously.

With the future operation of the extension, upgrading/replacing certain E/M systems across a large part—or even the entirety—of Lines 2 and 3 will be necessary, without which further extensions would not be possible.

For this reason, the project tender also includes the upgrade and/or replacement of the digital data transmission system across all operating stations of Lines 2 and 3. These modifications will require new equipment and software both at the existing Control Center at Syntagma and locally at stations and shafts. However, integration with the current systems has been planned so that there will be no interruption to the operation of Lines 2 and 3.

The extension will cover the route beyond the “Anthoupoli” Station toward the areas of Ilion and Agios Nikolaos, and in the future further toward Acharnes, and has been designed with the aim of:

• Serving many densely populated areas of the western suburbs.
• Increasing future interconnectivity of Metro lines, with a planned interchange at the “Ilion” Station with the future extension of Line 4 toward Petroupoli.

The new stations will be:

• Palatianí Station: Located at the intersection of Thivon and Andrea Papandreou streets, with two entrances on either side of Thivon Street.
• Ilion Station: Located at the intersection of Thivon and Elaion streets, with two entrances on either side of Thivon Street and provisions for connection/transfer with the station of the future Line 4 extension toward Petroupoli.
• Agios Nikolaos Station: Located beneath part of Agios Nikolaos Street and part of the landscaped green area between Paramythias, Olynthou, Zitsis, and Agios Nikolaos streets.

At Palatianí, a park-and-ride transfer station is also expected to be constructed in an adjacent area next to Palatianí Station, between Andrea Papandreou and Ikoniou streets, featuring a three-level underground parking facility with capacity for 150 private vehicles and direct connection to the station. At ground level, upon completion, a bus transfer hub is planned.

This section of Line 2 up to the Agios Nikolaos area is estimated to serve at least 67,000 passengers daily, while approximately 42,000 residents within a 500-meter radius of the three new stations will be served, along with around 5,000 jobs.

Line 4 – Future Extensions – Branches B–E

The new Metro Line 4 of Athens will not be limited to Section A “Alsos Veikou–Goudi,” as plans include its extension to other areas.

The next prioritized project concerns construction of the “Goudi–Lykovrysi” section, with stations at Goudi, Katechaki, Faros, Filothei, Sidera, Olympic Stadium, Paradeisos, OTE, Marousi, Pefki, and Lykovrysi.

The line will run along Kifisias Avenue, which suffers from severe daily traffic congestion. This project is expected to end the isolation from fixed-rail transport of residents of the northern suburbs and employees of the hundreds of companies located along this major arterial road.

This section will serve the OAKA Olympic Complex and the area’s commercial hub, and will terminate near the National Road at the “Lykovrysi” station.

The current Athens Metro Lines Development Plan includes Line 4, Alsos Veikou–Evangelismos–Faros–Marousi, with extensions (a) toward Vyronas/Upper Ilioupoli and (b) toward Petroupoli and the National Road. Line 4, U-shaped, consists of two radial branches toward Galatsi and Marousi and a central section passing through central Athens. It has a total length of 38.2 km, includes 35 stations, and is divided into five distinct sections (A–E):

• Section A: Alsos Veikou–Goudi (12.8 km, 15 stations)
• Section B: Goudi–Marousi (9.6 km, 8 stations)
• Section C: Evangelismos–Upper Ilioupoli (4.1 km, 3 stations)
• Section D: Alsos Veikou–Petroupoli (7.5 km, 6 stations)
• Section E: Marousi–National Road (4.4 km, 3 stations)

Future Extensions in Attica

Planning extensions is another major part of the company’s work. In Athens, responsibility for this level of planning lies with OASA. Currently, it is conducting the Attica transport study, which will determine the design, feasibility, and viability of Metro network extensions.

At the same time, studies have already begun for connecting the Stavros Niarchos Foundation Cultural Center to the existing Metro network, while the national plan continues to include the Metro extension toward Glyfada and the extension of Line 4 in both directions.

The westward extension of Line 4 from “Alsos Veikou” toward Agioi Anargyroi and Petroupoli is under study, passing through Nea Ionia and Nea Filadelfeia and the AEK stadium.

Similarly, the northward extension of Line 4 from “Katechaki” toward Marousi, Pefki, Lykovrysi, and the National Road is being examined.

The underground northward extension of Line 1 from “Kifisia” toward Nea Erythraia and the National Road (Varibobi interchange) is also being investigated.

New lines currently under study require further maturation and are contingent upon funding.

Priority is given to the extension of Line 4 toward Marousi and the National Road via Kifisias Avenue, as well as the new directions of Line 2 toward Glyfada.

In the southern sector, the final alignment of the extension toward Glyfada is being examined. The proposal foresees two branches: one toward Upper Glyfada and the other toward central Glyfada via the Ellinikon area. With this addition, the Metro will, for the first time, have two branches on the same line. The project requires further study maturation and secured funding.

Priority is also given to extending Line 4 toward Marousi and the National Road via Kifisias Avenue.

With these extensions, Athens aims to surpass the milestone of 100 Metro stations for the first time.

The Three Prioritized Extensions

1. Extension of Line 2 toward Ilion, with three new stations, already in the tendering process.
2. Extension of Line 2 toward Upper Glyfada, with two stations, and a new branch toward central Glyfada via Ellinikon, with two additional stations. This project requires further study maturation and secured funding.
3. Extension of Line 4 toward Marousi–National Road, including 11 new stations along the entire northern arc. This project also requires further study maturation and secured funding.