Stuttgart is the capital and largest city of the German state of Baden-Württemberg. It is located on the Neckar river in a fertile valley known as the Stuttgarter Kessel (Stuttgart Cauldron) and lies an hour from the Swabian Jura and the Black Forest. Stuttgart has a population of 635,911, making it the sixth largest city in Germany. 2.8 million people live in the city’s administrative region and 5.3 million people in its metropolitan area, making it the fourth largest metropolitan area in Germany. 4K Resolution.