In 1990 a partnership treaty between the towns Neckarsulm and Zschopau was agreed on.
Neckarsulm, lying at the estuary of the Rivers Sulm and Neckar, is an industrial and winetown.
As a former colony of Franconia at the Sulm it was first mentioned in a donation document of the monastery "Lorsch an der Bergstraße" in 771. It received its town Charter and market rights around 1300. Then in 1335 the town belonged to the electorate Mainz and in 1484 to the "Hohen Deutschorden" (a former tenure of the Earl of Weinsberg). Till today the town's coat of arms has got the colours and the cross of the "Deutschorden " town.
At the beginning of the 17th Century the ancient name Sulm was changed into Neckarsulm. With the secularisation and the formation of the Kingdom of Wuerttemberg Neckarsulm became a part of it and was a district town till 1938. Since then it has been the biggest Community in the administrative district of Heilbronn.
At the end of the 19th Century the change from a winetown to a modern industrial town began.(e.g.companies like AUDI; Kolbenschmidt): Since January lst in 1973 it has been a great district city, integrating the communities Dahlenfeld and Obereisesheim in the years 1971/72.Both are parts of the town with an own local constitution.
Sights are the St. Dionysius Parish Church, a castle, the German Bicycle Museum, the Lion Fountain and the rebuilt Marketstreet, the Capucin's Crypt and the market Square with the old and new townhall and the "Heilbronn Gate". In the last years Neckarsulm has also become known as the "Solar City" in Europe because of its innovative solar objects.