Greek National Road 1 is the longest highway in Greece. The highway begins at Kifissou Avenue or north of the Bay of Phaliro up to Efzoni at the border with the Former Yugoslav Republic of Macedonia, where it continues as the M1. Before the European routes numbers were changed, the northern part from Efzoni to GR-2 was E5N. Today, the entire road is part of E75. The job of maintaining and charging for parts of the motorway has recently been ceded to private consortiums, originally as part of the deal for the construction of the Ionia Odos. Each of them currently enforces a different tolling policy; from Athens to Maliakos Bay drivers pay twice northbound and once southbound, while on the part from northern Maliakos up to the intersection with E90, called the Aegean Motorway, drivers pay four times on both directions.

The part west of downtown Athens runs over the Cephisus river and Kifissou Avenue. From north of the boundary of Voiotia - Phthiotis, up to near Velestino, the tollway runs next to the bays and gulf which are adjacent to the Aegean. It then continues north of the Tempe Valley and up to the junction of the E90. It then shares a 25km common part with Egnatia Odos / E90 (on a west-east direction), and then, at the "Axios Interchange", continues north to Evzoni and the border of the FYR Macedonia. Its total length is approximately 553 km.

History

It used to be entirely a 2-lane highway and ended near Katerini until 1973. The section Athens - Lamia opened in August 1962 as a 14 m width road. The section Lamia - Larissa opened in October 1967 as a 14 m width road. The section Larissa - Katerini opened in September 1959 as a 13 m width road (except the Tempi valley pass opened as 10 m road). The section Katerini - Thessaloniki opened in September 1973 as a 14 m width road. The section Axios junction - Evzoni (border) opened in July 1973. The section Axios junction - Polykastro opened as a 14 m width road, while the section Polykastro - Evzoni (border) opened as a highway.

When it was extended to Thessaloniki and to the border with the FYR Macedonia, the highway had 4-lanes. It was extended during construction in the north in the 1980s and the south in the early and mid 1990s which began near the Afidnes toll. In 1995 the Greek National Road 1 had motorway characteristics in sections Athens - Thebes and Kleidi - Thessaloniki, while the section Thebes - Kleidi was an undivided 14 m road. In 1998, the motorway had 6-lanes up to north of Thebes, and 4 lanes from Thebes up to the Tempe Valley with a few sections at western Magnesia still having 2 lanes. Since then, the Larissa bypass has been constructed. As of 2005 it complies with all motorway standards for most of its length, except for 78 km around the Maliakos Bay and 25 km through the Tempe Valley, further to the north. Plans are underway to upgrade to motorway status at these parts with bypasses at the Maliakos Gulf part, and new tunnels at the Tempe Valley part. Construction of the Maliakos part is almost complete, with only the Thermopylae, Lamia, and Stylida bypasses still unfinished. . The tunnels at Tempe will be complete by 2012.

Interchanges

The toll motorway passes through towns and cities, which are ordered from south to north below. The exits are still unnumbered even though they are posted in some cases:

• Posidonos Avenue: the motorway starts at an interchange with this avenue, close to Pireas
• Attiki Odos (8th km) - interchange
• Tatoiou Street - interchange - 12th km
• Interchange with Lykovryssi and Athens' Sewage Plant - 14th km
• Interchange with the old Olympic Village- 15th km
• Interchange with Kifissia (from northbound) - formerly an intersection - 16th km
• Ekali-Varybobi (Nea Eritrea) (17th km) - interchange
• west of Agios Stefanos (21st km)
• Varybobi - Agios Stefanos interchange (25th km)
• near Afidnes and the Aphidnes toll booth/station and to Varybobi (northern part) (28th km)
• Interchange to Kalamos
• Interchange to Malakasa and Skala Oropou as well as Avlona (rarelt Greek National Road 79)
• Interchange to Oinofyta and Dilessi
• Schimatari Tolls
• Schimatari Interchange - access to Euboea and Tanagra (GR-44)
• Eleon Interchange - access to west of Chalkida and to Euboea
• Thiva Interchange - north and east of Thiva/Thebes (GR-3)
• Kastro Interchange
• Martino Interchange, access to Atalanti
• Malesina Interchange
• Tragana Interchange
• Skala Interchange
• Livanates Interchange
• Arkitsa Interchange
• Agios Konstantinos Interchange
• Regkinio Interchange
• Construction zone - westward
• Future junction with an unplanned tunnel
• Kamena Vourla Interchange
• Skarfeia Interchange
• Molos Interchange
• Mendenitsa Interchange
• Amfissa Interchange (GR-27)
• Lamia (208th km) - (GR-3) - old national road
• Lamia North (213rd/214th km) - (GR-28 (Agrinio - Karpenisi Lamia Road)
• Stylida Interchange
• Raches Interchange
• Pelasgia's Toll
• Agioi Theodoroi Interchange
• Almyros-Efxinoupoli Interchange
• Krokio Interchange
• Mikrothives Interchange (GR-30)
• Velestino/Volos (first constructed as two separate interchanges) - (GR-6, GR 30 and GR-34)
• Rizomylos Interchange
• Myra Interchange
• Nikaia/Larissa South - with the old National Road and [to GR-3 and GR-6
• Melissochori/Larissa East (GR-6 (Larissa - Trikala Road)
• Akro/Larissa North Interchange - with the old National road and to GR-3 of the Larissa north By-Pass (Elassona, Tirnavos and Kozani)
• Evangelismos
• former road junctions
• Tempe Toll
• the Tempe Valley (2-lanes)
• Platamonas Interchange
• Skotina Interchange
• Leptokarya Toll
• Leptokarya Interchange
• Litochoro Interchange
• Dion Interchange
• Nea Efesos Interchange
• Katerini Centre Interchange (GR-13 (Katerini - Elassona Road)
• Katerini-Paralia
• east of Katerini
• Korinos Interchange
• Makrygialos Interchange, serves to Sfendami and Pydna
• Methoni Interchanges, also serves to Nea Agathoupoli
• Aiginio Interchange
• Aliakmon River
• Kleidi Junction, junction of E90/GR-4, the via Egnatia (west)
• junction of E90 to Thessaloniki
• Loudias River, Imathia - Thessaloniki prefectural boundary
• Nea Malgara Interchange
• Nea Malgara Tolls
• Axios River
• Axios Junction - junction of Via Egnatia to Thessaloniki and the bypass
• Chalastra Interchange
• Gefyra Junction - junction with GR-2 (Edessa - Thessaloniki Road)
• Vathylakos Interchange
• Prochoma Interchange
• Polykastro-Kilkis Interchange
• Evzoni Interchange, near Evzoni
• International border with the FYR Macedonia (access with M1)