The project of Thessaloniki Metro included construction of an approx. 9.6 km-long line (the central section of the new line), which passes underground, below the main road arteries and the city centre. Part of the project were also the construction of 13 stations, a 50,000 square meter depot for rolling stock together with a workshop for maintenance and repair of mechanical and electrical equipment.

The Thessaloniki Metro is fully automated and equipped with an on-board assistant and will operate with CBTC (Communications-Based Train Control) signaling technology.

Sustainability and Archeology

An estimated 315,000 passengers are expected daily, equivalent to a daily reduction of about 212 tons of CO₂ emissions and approximately 60,000 fewer cars on the road each day. 

Subsurface discoveries - including many marble slabs from the famous Roman road known as the decumanus maximus near Aghia Sofia Station - made the construction of the metro line more complex. To avoid damaging these findings, the tunnels were built at a depth of about 20 meters. Covering an area of 30,000 square meters, it is the largest archaeological excavation in the city. 

Museum Stations were created, and some stations were redesigned during construction to protect and highlight the artifacts uncovered. At Venizelos Station, design modifications were necessary to preserve and manage the uncovered remains, while Demokratias Station was shifted 10 meters to place the archaeological finds above a Byzantine-era wall discovered during excavation.