The tradition of brewing beer in Germany reaches back many centuries. The breweries in the region are justifiably proud of their beer as well as the so-called Reinheitsgebot (Purity Decree) from 1516, an early consumer protection initiative. Or perhaps just one way to protect the brewers.
The law states that no foreign substances may be present. It took aggressive counter initiatives to allow beers to be sold from other countries that do not reach such high standards. Either way, the local dark beer traditionally brewed in Düsseldorf is some of the tastiest available..
The same excellent beers on tap in the breweries are also available from barrels in many pubs (Ausschank) across Düsseldorf.