Thessaloniki is the second-largest city in Greece and serves as the primary urban center of Northern Greece. With a metropolitan population exceeding one million inhabitants, it functions as the capital for the geographic region of Macedonia, the administrative region of Central Macedonia, and the Decentralized Administration of Macedonia and Thrace.
Historically, the city is recognized by its Greek name, i Symprotévousa, which translates to "the co-capital." This title refers to its significant historical status as a "co-reigning" city of the Byzantine Empire alongside Constantinople.