Esslingen am Neckar is a city in the Stuttgart Region of Baden-Württemberg in southern Germany, seat of the District of Esslingen as well as the largest city in the district.It is located on the Neckar River, about 14 kilometres (9 miles) southeast of Stuttgart city centre. The regions surrounding the city of Esslingen are also mostly developed.Esslingen was a free imperial city for several centuries until it was annexed by Württemberg in 1802.