The initial construction period ended in 1689, and, of the buildings from that time, the Commandant's Quarters and the Bakery still stand today. The fortress's main task was to secure the old ferry crossing and surrounding fields from a Swedish invasion from the east. The fortress was intended to prevent the enemy from advancing further into Norway and continuing south-west towards the capital (Christiania).
Today, Kongsvinger Fortress consists of the main fortress dating from the 17th to 18th centuries and the foreground area with more recent buildings. Of all our fortresses it is the best-preserved Baroque fortress; its principal element is its jagged wall and demi-bastions that have been adapted to the uneven terrain.
There are a number of buildings dating from the 17th and 18th centuries: They are made of stone, mostly granite and natural stone, except for the Commandant's Quarters from 1883, a panel-clad, half-timbered building. The barracks from the 1770s is the only building predominantly built of brick. There are two more recent buildings in the foreground area, one of which was built as recently as 2000.
Outside the fortress itself, various buildings have stood over the years, but now only the Outer Guardhouse, the Laboratory and the Powder Magazine from 1811 remain.
The fortress reached the height of its importance during the period from 1808 to 1814. When, during the Napoleonic Wars, the Kingdom of Denmark-Norway again became involved in a conflict with Sweden, there was greater focus on the risk of the fortress coming under attack. The fortifications at Kongsvinger also had a central place in the plans to defend Norway against Sweden in 1905, and two forts were built near the fortress, one of which was the well-preserved Vardefortet from 1903.
This fort consists of an underground chamber with two concrete cannon emplacements with a command post, surrounded by trenches and barbed wire. During World War II, the fortress was used as a course venue by the occupying forces. The Germans carried out a number of building works and the influence from this period can still be seen in the interior of the building known as the 'Slave Quarters'.