The 10 km-long, east-west underground line has two, single-track tunnels connecting 13 stations and is expected to carry 313,000 passengers a day in this city of about a million people. An eastward extension of the line with five additional stations is scheduled to open in 2025. A westward extension is planned. But it will likely take several more years for the metro to reach the city’s busy Macedonia Airport.

Passengers entering the Eleftherios Venizelos station in the city center can take a look at some of the more than 300,000 artifacts dug up by archaeologists. Deep underground, remains of the city’s busiest street in the 6th century were found.

The line has cost about EUR 3 billion (US$ 3.16 billion). It received EUR 650 million (US$ 685 million) from the European Investment Bank and just over EUR 407 million (US$ 429 million) from the European Regional Development Fund. Thessaloniki's metro system, constructed by Webuild with partners Hitachi and Greek firm Aktor, will be operated by Thema, a joint venture between Italy's ATM (51%) and French infrastructure group Egis (49%). Thema secured an 11-year management contract in June 2023.