Although Silkeborg city was not formally founded until 1844, the history of the city can be traced back to the 15th century. At this time a castle was located at an islet in the lake of Silkeborg, and it was probably due to this castle that the city name originated, as Silkeborg in English can be translated into ‘silk castle’. The castle does not exist today but excavations can be seen on the castle islet about 1 km from the town square.In 1844 the two paper manufacturing brothers Christian and Michael Drewsen of the corporation Drewsen og Sønner moved from Copenhagen to Jutland to start a paper mill. Next to the Gudenå River, close to the spot of the former Silkeborg castle, the brothers opened Silkeborg Papirfabrik (Silkeborg Paper mill), as the idea was to use the water power as energy source, as a resource for paper production, and the river as a transport route. The youngest brother, Michael Drewsen, was responsible for the daily management of the mill, and he was later to be acknowledged as the founder of the city. Today a statue of Michael Drewsen can be seen in front of the old city hall at the town square of Silkeborg.