Attiki Odos () (Attica Road) is a toll motorway system in Greece. The Attiki Odos motorways form the outer beltways of the Greater Athens metropolitan area. The total length of the motorways is . The Attiki Odos system currently consists of the following motorways:
- A6: Eleusis - Athens International Airport
- A62 (Ymittos Ring): Katechaki Avenue - Pallini
- A621: Doukissis Plakentias Avenue - Agia Paraskevi
- A64: Koropi - Athens International Airport
- A65 (Aigaleo Ring): Skaramagas - Ano Liosia
History
Construction of the A6 motorway began in 1996. Part of it was opened, along with the Eleftherios Venizelos International Airport to which it connects, in March 2001.
thumb|Highway interchange in the northern suburb of [[Maroussi.]]
In early 2003, the A6 was opened from Kifisias Avenue Interchange to Eleftherios Venizelos Airport; the Ymittos Ring was almost paved by this time, and tunnels were already complete. On 3 September 2003, the Ymittos Ring opened. This part of the motorway runs in the northern part of the Hymettus hills and bypassed Mesogeion Avenue and linked to Kifissou Avenue and its suburbs, and the Airport along with the eastern suburbs of Athens.
thumb|200px|Westbound to [[Elefsina.]]
thumb|200px|Attiki Odos at night.
In November 2003, the western part opened from the junction with A8 motorway to Kifisias Avenue. In April 2004, a small 2.5 km section opened, connecting the Ymittos Ring to the westbound direction of the A6.
thumb|200px|Interchange at the Attiki Odos Airport Entrance.
Safety
Attiki Odos is considered one of the safest motorways in Europe. Its design used strict safety-related technical specifications, including updated hard shoulders in both directions and high quality skid-resistant asphalt pavement, dense lighting and fencing. Attiki Odos has hundreds of CCTV cameras connected to the Traffic Management Centre (TMC), which detects any incidents occurring on the motorway and informs the intervention and maintenance patrol units to provide assistance. Other sophisticated safety systems include:
- Road pavement sensors
- Carbon monoxide measurement systems installed in tunnels
- TETRA system for communication with the patrol units
- Electronic variable message signs
- Automatic tunnel ventilation systems
Operation and maintenance
Nea Attiki Odos is the current operator of Attiki Odos: it replaced Attiki Odos S.A. as the network's concessionaire on 6 October 2024.
Since 8 October 2024, Nea Attiki Odos is a consortium of GEK Terna as the majority shareholder (90%), and Marianna Latsis (via Latsco Direct Investments) as a minority (10%). Nea Attiki Odos' predecessor, Attiki Odos S.A, was a consortium of: Aktor Concessions, then part of Ellaktor (65.75%); the Avax Group (34.21%, of which 10.02% was held by their subsidiary ETETH); and Egis Projects (0.04%).
Tolls
Article 50 of the concession contract, as ratified by Law 2445/1996, requires drivers to pay a toll to use the A6, A62 (Hymettus Ring Road) and A621. The toll, paid once when entering the motorways, is the same regardless of distance travelled, but depends on the vehicle category and payment method: , the single journey toll is €1.40 for motorbikes, €2.80 for cars and vans, €7.10 for trucks and buses, and €11.30 for heavy goods vehicles.
Drivers can pay by cash, credit or debit card, e-pass or a special account card: e-pass transponders from other motorways are accepted under the Greek Interoperable Tolling System (GRITS), which was introduced in 2012 and expanded nationwide in November 2020.
thumb|200px|Attiki Odos coming through [[Maroussi|Maroussi Metropolitan Suburb, outside Athens Mall.]]
Expansion plans
In 2001, the same year the first section of the motorway was delivered, the discussion about the extension of the motorway first opened, but the plans remained unimplemented for many years.
On October 21, 2005 a new expansion plan was proposed. 76 km of motorway was to be constructed, bringing the total length to 141 km. Extensions were to be constructed towards Rafina, Lavrio and Vouliagmeni. The Hymettus Beltway was also to be extended southwards to Vouliagmeni, in the area of Elliniko. In 2010 and 2013 alterations in the original planning were made and more extensions were proposed.