Pforzheim is a town of nearly 119,000 inhabitants in the state of Baden-Württemberg, southwest Germany at the gate to the Black Forest. It is world-famous for its jewelry and watch-making industry. Because of that it gained the nickname "Goldstadt" or Golden City. It has an area of 98 km² and is situated between the cities of Stuttgart and Karlsruhe at the confluence of three rivers (Enz, Nagold and Würm) and marks the frontier between Baden and Württemberg, being located on Baden territory. The City of Pforzheim does not belong to any administrative district (Kreis), but at the same time, it hosts the administrative offices of the Enz district surrounding the town. During World War II, Pforzheim was bombed a number of times. The largest raid, and one of the most devastating area bombardments of World War II, was carried out by the Royal Air Force (RAF) on the evening of February 23, 1945. About one quarter of the town's population, over 17,000 people, were killed in the air raid, and about 83% of the town's buildings were destroyed. The town was thought by the Allies to be producing precision instruments for use in the German war effort and to be a transport centre for the movement of German troops. After the war, the rubble from the destruction was heaped into a large pile on the outskirts of the town, as was done by other cities such as Stuttgart and Munich. A building called the "Wallberg" was erected as a concrete "cap" on the mountain of rubble, long since covered with earth and vegetation. In the twenty years following the end of the war, Pforzheim was gradually rebuilt, giving the town a quite modern look.