Thessaloniki, also known as Thessalonica and historically known as Salonica, is the second-largest city in Greece and the capital of the region of Central Macedonia as well as the capital of the Decentralized Administration of Macedonia and Thrace. Its honorific title is Συμπρωτεύουσα (Symprotévusa), literally "co-capital", and stands as a reference to its historical status as the Συμβασιλεύουσα (Symvasilévousa), "co-reigning" city of the Byzantine Empire, alongside Constantinople. According to the 2011 census the municipality of Thessaloniki today has a population of 322,240, while the Thessaloniki Urban Area (the contiguous built up area forming the "City of Thessaloniki") has a population of 790,824; making it the fifth largest and most populated city in the Balkans and the second most populated city that is not a capital. Furthermore, the Thessaloniki Metropolitan Area extends over an area of 1,455.62 km (562.02 sq mi) and its population in 2011 reached a total of 1,006,730 inhabitants. Thessaloniki is Greece's second major economic, industrial, commercial and political centre, and a major transportation hub for the rest of southeastern Europe; its commercial port is also of great importance for Greece and the southeastern European hinterland. The city is renowned for its festivals, events and vibrant cultural life in general, and is considered to be Greece's cultural capital. Events such as the Thessaloniki International Trade Fair and the Thessaloniki International Film Festival are held annually, while the city also hosts the largest bi-annual meeting of the Greek diaspora. In 2014 Thessaloniki will be the European Youth Capital. Founded in 315 BC by Cassander of Macedon, Thessaloniki's history spans some 2,300 years. An important metropolis by the Roman period, Thessaloniki was the second largest and wealthiest city of the Byzantine Empire. Thessaloniki is home to numerous notable Byzantine monuments, including the Paleochristian and Byzantine monuments of Thessaloniki, a UNESCO World Heritage Site, as well as several Roman, Ottoman and Sephardic Jewish structures. The city's main university, Aristotle University, is the largest in Greece and the Balkans. In addition to its historic roots, Thessaloniki is also a very popular tourist destination in Greece. In 2010, Lonely Planet ranked Thessaloniki as the world's fifth-best party city worldwide, comparable to other cities such as Dubai and Montreal.

Source: wikipedia.org