Frederiksværk is a town in North Zealand with 12,694 inhabitants (2020), located between Arresø and Roskilde Fjord. The city is located in Halsnæs Municipality in the northwestern part of the Capital Region.


The history of the city
When the flying sand had blocked both Arresø's old connection with the Kattegat to the north and later its connection with the Isefjord, Frederik IV had a canal 1717-19 dug by Danish soldiers under the command of Major Eberlin v. Feriden. After an old tradition, however, it was Swedish prisoners who carried out the work, and this may also be true, as Swedish prisoners often went into Danish service or were put to work and even rented out to landowners. The canal was the precondition for the construction of large factory facilities that utilized hydropower. At the same time, the town of Frederiksværk emerged.

Early factory trials
In 1728, Frederik IV entrusted overland builder Johan Kornelius Krieger to build an agate grinder by the canal. The mill was taken into use in 1729, but it was already closed down immediately after the death of Christian VI in 1746. In the following years, there were plans to transform the mill into a leather factory, which, however, did not materialize. On the other hand, in 1751 the king took over a larger stretch by the river and left it to the Frenchman Etienne Jandin de Peyrembert to build a cannon plant here. Although the king fired significant sums into the project, the work of producing usable cannons failed. In 1756, Frederik V donated the agate mill to State Councilor Just Fabritius and Chancellor, later Major General, Johan Frederik Classen with associated more than 90 acres of land. Area was later expanded on the condition that the two contractors would build a gunpowder plant. In 1758, the first powder was produced at the plant, which was named Frederiksværk. To provide hydropower for this industry, the canal that bends north from the river that carries the water from Arresø to Roskilde Fjord was excavated. At the entrance to the gunpowder plant, the canal was bent to the west and continued until it emptied into the fjord; at the bend, a bulwark with a lock was built, so that the water could be led, and stamp and core mills built on the site. In addition, the two companions set up a cannon foundry and were thus able to supply both gunpowder and cannons to the army during the current and dangerous Prussian Seven Years' War, which is why they were strongly favored by the state.


Johan Frederik Classen
Fabricius resigned from the company in 1760, after which the work passed into actual state property with the king's purchase of Frederiksværk for 130,000 rigsdaler. But the autocratic majesty let Classen continue to control it by both retaining the inspection and, as it was called, "that he may thus, at his own pleasure, bark and roll as he pleases." Finally, after a futile attempt to get Frederiksværk (together with Kronborg Geværfabrik) subsidized for free, Classen became the sole owner of the plant for a purchase price of 100,000 rigsdaler. Favorable trade conditions, especially during the North American War of Independence, and great hospitality on the part of the king, enabled Classen to accomplish much, so that not only his factories flourished, but the whole place and region prospered; he successfully had the whole sandy terrain planted, which not only provided enough wood for the gunpowder mills, but also provided shelter for the city. He also worked as an avid farmer: he owned large tracts of land around the town. The peasant estate, which he acquired in 1768, amounted to 798 acres of hard grain land. Here he received permission to establish the main farms Arresødal and Grønnessegård.

A central part of the cannon work was Gjethuset. This foundry was built in two stages. The north wing was completed in 1764, while the three-wing industrial building was completed in 1769. The foundry still exists; after a period of severe decay in the latter half of the 20th century, the Gjethuset and the area around it were restored in a large-scale construction project in the early 1990s and today serves as a culture house.

After Classen's death at Arresødal on 24 March 1792, according to a provision in his will, Frederiksværk's establishment with buildings and machinery as well as the two estates Arresødal and Grønnessegård were transferred to Count Carl of Hessen, in exchange for him paying 7,000 rigsdaler annually to Classen by the will. created fideicommiss. In the year 1804, the county count transferred Frederiksværk, whose debt had grown, so that it exceeded the value of the property, and the estates to his son-in-law, Crown Prince Frederik (later Frederik VI). The Crown Prince set up his own administration until the properties could become state property after the co-heirs were released. These negotiations lasted throughout the reign of Frederik VI and were not completed until the beginning of Christian VIII (1840).

In 1833, cannon production stopped. It is estimated that a total of between 2,500 and 2,600 cannons have been produced in Frederiksværk.


Trading space

In the middle of the 19th century, Frederiksværk is described as a factory town with an iron foundry (90 workers), a machine factory (60 workers), a knife factory with a grinding mill (57 workers), a powder factory (27 workers) and a copper rolling mill (24 workers) and several smaller private companies from breweries to a "forging workshop for agricultural implements" as well as a few privileged trading companies.

In 1850, Frederiksværk was granted the status of a trading post. Despite this, the contemporary J.P. Trap skeptical about the place's trading opportunities. In the first edition of his statistical-topographical description of Denmark, he wrote: "About Frederiksværk, when the two aforementioned grocery entitlements had to be raised by the death of the owners or by replacement, could rise as a trading place in freer competition, is considered doubtful".

The fixtures are sold for private use
According to the law of 8 April 1851, the attachments were sold to private property 1854-55, Arresødal was sold in 1855, Grønnessegård in 1859.

Heegaard and the Land Military Service
According to the law of 4 May 1856 in 1857, the factories were sold to factory owner Anker Heegaard, who joined them on 1 January 1858 and ran them as a machine factory, iron foundry and enamel workshop, while the gunpowder factory was preserved as state property and transferred to the land military service.

The gunpowder plant was later subordinated to the director of the artillery's technical service and has been the army's main supplier since its construction. From 1884 it also supplied gunpowder to the navy. The oldest gunpowder manufactured was stamped powder gunpowder. In 1862, the old stamp mills were closed down, and the production of roller press powder (laminoir powder) was switched on. Later, gunpowder was produced by hydraulic pressing, then prismatic gunpowder, first black and later brown. The plant had supplied almost all of the brown gunpowder used to charge even the kingdom's heaviest coastal cannons. Finally, in 1891, the manufacture of smokeless gunpowder was introduced. A remote section was then built in Arresødal Skov by the lake, Sørups Vang, where a few operations at the non-smoking gunpowder manufacture took place. While the actual fabrication took place at the old gunpowder plant, where several new buildings were therefore erected.

The gunpowder mills were initially powered solely by hydropower. There were still around 1900 three water wheels, one of which was a turbine. However, as the number of turbines was significantly increased, and when hydropower did not strike, steam power was also introduced.

Frederiksværk's population increased at the end of the 19th century and the beginning of the 20th century. There lived 739 people in the city in 1850, 708 in 1855, 764 in 1860, 915 in 1870, 839 in 1880, 1,098 in 1890, 1,431 in 1901, 1,664 in 1906 and 1,672 in 1911.

Of the 1,664 inhabitants of Frederiksværk in 1906, 129 subsisted on intangible activities, 44 on agriculture, forestry and dairy farming, 42 on fishing, 945 on crafts and industry, 269 on trade and more, 109 on transport, 82 were retired people, 17 lived off public support and 27 by other or unspecified company.