Plovdiv is the second-largest city in Bulgaria, standing on the banks of the Maritsa river in the historical region of Thrace, behind the state capital Sofia. It has a population of 346,893 and 675,000 in the greater metropolitan area. Plovdiv is a cultural hub in Bulgaria and was the European Capital of Culture in 2019. The city is an important economic, transport, cultural, and educational center. Plovdiv joined the UNESCO Global Network of Learning Cities in 2016.