Leipzig is the largest city in the federal state of Saxony, Germany. With a population of 582,277 inhabitants Leipzig is located about southwest of Berlin at the confluence of the White Elster, Pleisse, and Parthe rivers at the southern end of the North German Plain. Leipzig has been a trade city since at least the time of the Holy Roman Empire. Leipzig later played a significant role in instigating the fall of communism in Eastern Europe, through events which took place in and around St. Nicholas Church. Since the reunification of Germany, Leipzig has undergone significant change with the restoration of some historical buildings, the demolition of others, and the development of a modern transport infrastructure. Leipzig today is an economic center and the most livable city in Germany, according to the GfK marketing research institution. Leipzig is currently listed as Gamma World City and Germanys "Boomtown". Outside of Leipzig the Neuseenland district forms a huge lake area of approximately .