A French cannon founder, Peyrembert, received permission to build a cannon factory here. Having gotten into difficulties, King Frederik V requested that his chancellery advisor, Johan Frederik Classen, take over the operation of the foundry. Under Classen's management the town blossomed, and there came a gunpowder mill, as well as light industry and handicrafts to the town. This resulted in Classen's being appointed major general. On 25 August 1756 the king issued a document permitting Classen to call the town "Friederichswerk". Classen was allowed to build a new foundry, Gjethuset, and it was constructed between 1761 and 1767. It has been used as a cannon foundry until 1928, and has been used for heavy industry until 1976. The building has been restored and reopened on 12 June 1996. It is now used as an art and culture center with theatre, music and art exhibitions. The original architect was either Lauritz de Thurah or Nicolai Eigtved. The word Gjethus comes from Low GermanGethus and means "foundry house". Classen's home in the neoclassical style, Arresødal, is still standing. It is in private ownership, but can be viewed from the outside.
Attractions
There are a number of churches from the Middle Ages in the villages near Frederiksværk. Vinderød Church, in the town of Frederiksværk, houses the sarcophagus of General Classen and has a view towards the Arresø.
Town Museum
The Town Museum is established in the old Arsenal, which was used as a storehouse for the cannons cast in Gjethuset. Displays in the museum concern weapon fabrication, gunpowder production and copper rolling during the years 1750 to 1900. There is also a restored grocery store from 1900.
The Gunpowder Mill Museum
The small open-air museum, part of the Industrial Museum Frederiks Værk, contains one of the world's best-preserved powder mills with buildings and working machines from 1800. There is also a working watermill on the premises.
GeoArt is located at the northern tip of Lake Arre, between Frederiksværk and Helsinge. It has an art gallery with changing exhibitions and a permanent exhibition of gems and minerals including 225 million year old petrified wood from Arizona, amethyst from Brazil and fluorite from China.
Frederiksværk municipality
Until 1 January 2007 Frederiksværk was also a municipality in Frederiksborg County on the island of Zealand in eastern Denmark, located between Lake Arre and Roskilde Fjord. The municipality covered an area of 90 km², and had a total population of 20,340. Its last mayor was Helge Friis, a member of the Social Democratspolitical party. Frederiksværk municipality ceased to exist due to Kommunalreformen. It was merged with existing Hundested municipality to form the new Frederiksværk-Hundested municipality. The name was changed to Halsnæs Municipality on 1 January 2008. This created a municipality with an area of 120 km² and a total population of c. 30,253.
Municipal information
The municipal Frederiksværk contained many small towns and villages besides the city of Frederiksværk, including Ølsted, Kregme, Liseleje, Asserbo and Melby.
Notable people
Johan Frederik Classen a Danish-Norwegian industrialist, major general, landowner and founder of Det Classenske Fideicommis