Cologne is Germany's fourth-largest city (after Berlin, Hamburg and Munich), and is the largest city both in the German Federal State of North Rhine-Westphalia and within the Rhine-Ruhr Metropolitan Area, one of the major European metropolitan areas with more than ten million inhabitants. It is one of the oldest cities in Germany, having been founded by the Romans in the year 38 BC. The name is derived from that of the Roman settlement, Colonia Claudia Ara Agrippinensium.
Erfurt is the capital city of Thuringia and is the main city nearest to the geographical centre of Germany, located 100 km SW of Leipzig, 150 km N of Nürnberg and 180 km SE of Hannover. Erfurt Airport can be reached by plane via Munich. It lies in the southern part of the Thuringian Basin, within the wide valley of Gera River, a tributary of the Unstrut. To the south, the city is surrounded by the hilly forest of Steigerwald.
Elbląg is a city in northern Poland with 127,892 inhabitants (2006). It is the capital of Elbląg County and has been assigned to the Warmian-Masurian Voivodeship since 1999. Before then it was the capital of Elbląg Voivodeship (1975–1998) and a county seat in Gdańsk Voivodeship (1945–1975). The city is a port on the river Elbląg which flows into the Vistula Lagoon about 10 km to the north, thus giving the city access to the Baltic Sea via the Russian-controlled Strait of Baltiysk.
Gdańsk, formerly known by its German name Danzig, is a city on the Baltic coast in northern Poland, at the centre of the country's fourth-largest metropolitan area. Gdańsk is Poland's principal seaport as well as the capital of the Pomeranian Voivodeship. It is also historically the largest city of the Kashubian region.
Hamburg is the second-largest city in Germany and the eleventh-largest city in the European Union. The city is home to approximately 1.8 million people, while the Hamburg Metropolitan Region has more than 4.3 million inhabitants. The port of Hamburg is the second-largest port in Europe, and the ninth largest in the world. Hamburg's official name is the Free and Hanseatic City of Hamburg .