Attica Ring Road: Kymis Avenue Expansion Project Set for Key Developments in 2026

2026 is shaping up to be a pivotal year for the first planned extension of Attiki Odos, specifically the expansion of Kymis Avenue.

The Council of State’s ruling on the appeal—heard at the end of last year—is expected to take several months. According to Heraklion Mayor Nikos Babalos, who spoke at a recent conference, the decision is likely to be announced by the end of the year.

It’s worth noting that the municipality is requesting a greater portion of Kymis Avenue to be constructed underground in order to minimize the nuisance caused by the daily passage of thousands of vehicles. However, if the appeal is upheld, it will require changes to the current design and environmental terms of the project, along with a significant increase in cost.

The forthcoming decision by the Council of State is particularly crucial, as a green light would allow the tender process to proceed and ultimately be completed. Conversely, if the ruling is in favor of the appeal, the future of the project’s tender is brought into question.

However, the legal proceedings are not the only obstacle to the implementation of the Kymis Avenue extension. Depending on how the situation unfolds, the issue of funding will also be critical, as the project is still seeking financial resources. The awarding authority for the project is the Ministry of Infrastructure and Transport.

Therefore, depending on whether the decision is positive or negative, it will also determine how the project’s necessary funding will be secured. The tender process for this project has been ongoing since 2022, and a key condition for completing it is that the Contracting Authority must not proceed with awarding the contract before the project is included in a co-financing program.

It is worth recalling that the selected contractor consortium is TERNA–AKTOR–INTRAKAT, which emerged as the preferred bidder in the tender. If the process moves forward and the project is implemented, it will mark the first extension of Attiki Odos since 2004, when the main axis became fully operational.

That said, the total cost of the project, including VAT, amounts to €352.3 million (€284.3 million excluding VAT). The tender was launched on February 22, 2022, and concluded relatively quickly within the same year.

The construction period for the Kymis Avenue extension is set at 48 months from the signing of the contract. If the project proceeds and the contract is signed within 2024, the new roadway is expected to be operational by late 2028.

The most important road project in Attica

The existing Attiki Odos awaits the extension of Kymis Avenue, as it is considered the most important road project in Attica. The project will create a bypass for the “congested” section of the Attiki Odos and help relieve pressure on the Metamorfosi interchange, which currently bears the full traffic load to and from Kifisos Avenue.

This is effectively the first extension of Attiki Odos since its completion 20 years ago, and it concerns the extension of Kymis Avenue from the eponymous interchange to the National Road at the Kalyftaki interchange in Lykovrysi, providing an alternative route for users of the corridor.

It is also the first major road project for Attica nearly two decades after the 2004 Olympic Games. As already announced, a new expansion program is expected for the urban motorway, including the Ilioupoli Tunnel that will connect Katechaki Avenue with Vouliagmenis Avenue, as well as extensions to the ports of Rafina and Lavrio.

What is planned to be constructed

The project will be carried out within the administrative boundaries of the municipalities of Lykovrysi–Pefki, Iraklio, and Kifisia. Its objective is the completion of Kymis Avenue, in the section from Attiki Odos to the Kalyftaki Interchange on National Road No. 1, and involves the design and construction of a closed-access highway segment with a total length of approximately 3.8 km. The completion of the connection to the Kalyftaki Interchange on NR-1 is included as part of the optional contract scope. The total length of the project, including the option, is estimated at 4.2 km.

• The optional scope, valued at €32.53 million (including VAT) and included in the total cost of the project, concerns the completion of the Kalyftaki Interchange. The works include:
• Two bridges, each approximately 260 meters long, with a deck width of around 10 meters, which will carry the two directional ramps of the interchange.
• Bridge accesses, including the construction of retaining walls for the necessary embankments.

Construction of new road sections and ramps to replace the road network of the existing at-grade interchange.

The project also includes all ancillary works (pavement structure, asphalt layers, drainage ditches and pipelines, road lighting, signage, safety barriers, etc.).

The project will be funded in the near future through resources from the 2021–2027 NSRF (ESPA).

The works to be studied and constructed in detail include:

• Completion of the interchange works connecting Kymis Avenue with Attiki Odos.
• Open-road construction from the interchange connection of Kymis Avenue with Attiki Odos up to approx. chainage 0+360 (southern tunnel portal).
• Underground tunnel (indicative length of approx. 1.25 km).
• Tunnel constructed using the cut-and-cover method (indicative length of approx. 1.15 km).
• Open-road construction after the end of the cut-and-cover section up to approx. chainage 3+700, where the influence area of the Kalyftaki Interchange begins.
• Other accompanying works, including: connections to local road networks, at-grade intersections, service roads, stream management works, stormwater drainage systems, vertical and horizontal signage, vehicle restraint systems (VRS), fencing of roadworks, engineering structures (overpasses, culverts, retaining walls, etc.), electromechanical installations (road lighting, traffic signals, irrigation networks, etc.), environmental works, etc.
• Electromechanical installations for the underground sections (fire safety, fire suppression, ventilation, possible ventilation shafts, tunnel lighting, traffic signals, telephone systems infrastructure, tunnel service buildings, etc.).
• Landscaping works.
• Temporary road diversions and traffic arrangements during construction.

An optional scope is also foreseen, as detailed in Article 11 of the tender documents.

For more details and the complete article in Greek, click here