After discovering a relatively small part of Kungsholmen in the last few posts, we come back to the historical parts of Stockholm. In the post on Stockholm City Hall, I told you that its design was partially inspired by 17th-century palaces. This time, we visit a place whose history actually dates back as long as to the 1600s.

Kastellet in Stockholm

It is unknown when exactly the islands of Kastellholmen and Skeppsholmen were connected by a bridge for the first time. However, the available sources suggest that it was likely in the latter half of the 1640s as that was when a bridge started appearing on the maps. As was the case with several other islands belonging to Stockholm, the construction of a bridge meant urbanisation of the island simply because the access to it was now straightforward.

The purpose of Kastellholmen was pretty clear from the beginning, though. Probably around the 1660s a Swedish flag was placed on the top of the island to salute passing vessels. Since the island has been used by the military during the largest part of its modern history, it is not surprising that Stockholmers have not commonly visited this place. However, there was a period during which it became more popular which we will get back to later in the post.

Originally, the flag was only accompanied by a small cottage for the guard in the service. A few years after the flag had been placed on the island, the cottage was turned into an octagonal one-storey fort which was later used as a storage for gunpowder.

A few decades had to pass before the first stone building was built on the hill on Kastellholmen. It also served as accommodation for guarding officers and was enhanced by a battery for salute cannons several years after it had been completed.

At the beginning of the 19th century, a laboratory was created at the fort whose main task was to produce cartridges. It was this move that likely meant the end of the first stone fort at Kastellholmen. The fort blew up in 1845. According to the available sources, the actual cause of the explosion has never been discovered which is why we can only speculate if the laboratory had anything to do with it at all.

No time had been wasted as the exterior of the contemporary fort was completed already three years after the explosion. Since the very beginning of the discussions regarding the new fort, it was emphasised that the laboratory shall be separated from the main building. The works on the interior of the building were delayed because of the last significant cholera epidemic in Stockholm which erupted in 1848.

When the fort was finished, it was able to accommodate a total of 112 men. The first 58 moved in in 1850 but were relocated a year later due to unsuitable living conditions in the new fort. It is said that the rooms were too humid which caused a variety of health issues to the men living in the facility. Apart from the barracks, the fort was meant to be used for defence purposes if necessary. Sweden has not been at a war since the end of the Swedish-Norwegian War in 1814, though.

The so-called Kastellet is indeed not the only thing you will find on Kastellholmen. As you can imagine, there are several other military facilities left from the past. These include dwellings for the members of the Navy or the coal shed from the 1850s when the fleet started using steamboats.

However, I mentioned that the island became more popular among the general public too so let’s find out why. It once again started with the Navy when a new rule came into validity around 1840. The rule said that all men in the Navy were required to learn how to swim. This may seem strange today but apparently, not all members of the Swedish Navy could swim before 1840.

To allow men the necessary practice, a bathhouse was built on Kastellholmen. The idea was developed further when Nancy Ekberg decided to open a bathhouse for women, too. She received a permission from the authorities to open such bathhouse in 1848. Under the condition that there would be a roof ‘as it was for women,’ whatever the author of the letter meant by that. Ekberg, who had studied swimming baths in multiple European cities, allowed poor school girls to enter the bathhouse for free.

Eventually, the bathhouses were moved to Skeppsholmen some 20 years after the second one had been opened. The main reasons for this were the distance from the city to Kastellholmen and the quality of the water. The water itself used to be of poor quality and the proximity of a hospital where cholera patients were treated did not help people feel better either.

Skating pavilion (Skridspaviljongen) in Stockholm

The second half of the 19th century was, moreover, the time when winter sports became popular – especially among the royals. The tradition started in France with Napoleon III who used to go ice-skating on a lake in the Bologne Woods in Paris. It soon caught on among the Swedish upper class, too, which is why the Royal Skating Club was formed. The beautiful Skating Pavilion (Skridskopaviljongen) was built on Kastellholmen because the waters between this island and the nearby Skeppsholmen were used for ice-skating most often.

Kastellholmen is certainly not the island with the richest history in Stockholm when it comes to social affairs but it certainly has its beauties. The two most dominant buildings on the island, Kastellet and the Skating Pavilion, serve as offices and conference centres today and are absolutely worth your trip to the island. Even though 19th-century swimmers considered it to be too far from the city it is actually in the heart of present-day Stockholm so it will only take you a few minutes extra to visit the island if you already are in the city centre.

As always, we have a lot more stories for you ready that are going to be published here at Trevl in the coming days. When you decide to go out and explore the world, do not forget our app Trevl for Android where you will find many beautiful places to see and all the interesting stories they have to tell.

Wollin, Nils G., 1971. Skeppsholmen under 300 år.