Akershus Fortress

Akershus Fortress (Akershus festning) is a medieval stronghold in the heart of Oslo, rising above the fjord. Over the centuries it has served as a castle, a royal residence, a military fortress and a prison. Today it is among the most visited sights in the Norwegian capital, and entry to the grounds is usually free.

When was Akershus Fortress built?

Work on the castle and fortress began in 1299 under King Håkon V. The hilltop above the Oslofjord was a deliberate choice: it offered a commanding view of the sea approach to the city and controlled access to the harbour. In the following centuries the complex was extended and reinforced so that it could withstand sieges.

How did the castle change over time?

King Christian IV commissioned a major rebuilding. Under him the medieval castle was transformed into a Renaissance royal residence. Akershus therefore played a double role: a defensive stronghold on one hand, a ceremonial seat of the monarch on the other. In later periods some of the buildings were also used as a prison.

What happened here during the Second World War?

During the German occupation, Norwegian resistance fighters were executed by firing squad within the fortress. After the war, collaborators were executed at the same site. This chapter of history is remembered today in a museum on the grounds, so a visit is as much a reflective experience as an architectural one.

What can you see at Akershus?

• The castle, with its halls, castle chapel and royal mausoleum.
• The dungeons and royal rooms, open to visitors when no state visits, military ceremonies or other official events are taking place.
• The Armed Forces Museum (Forsvarsmuseet), covering the history of the Norwegian military.
• The Norwegian Resistance Museum (Norges Hjemmefrontmuseum), dedicated to the struggle against the occupiers in 1940-1945.
• Bastions and ramparts, with views across the harbour and the fjord.

The fortress is not only a monument. The grounds also house the headquarters of the Norwegian Armed Forces and the Ministry of Defence, so it remains a working state site.

Is there an entrance fee, and how do you visit?

Entry to the fortress grounds is normally free. In summer, guided tours are offered and start at the Fortress Visitor Centre. Opening hours for the museums and the castle change from time to time, so it is wise to check official channels before you go.

How much time should you plan?

A relaxed walk around the grounds, bastions and exterior views typically takes one to two hours. If you want to go inside the castle, including its halls, chapel and mausoleum, add at least another hour. Museum visitors should allow more.

How do you get there?

The easiest way is on foot from the city centre. You can also take tram line 12 to the Kontraskjæret stop, about 500 metres from the entrance.

Frequently asked questions

Do I need a ticket for Akershus? Not for the grounds, which are usually free, though some interiors and museums may charge admission.

Is the castle open every day? Not always. During state visits or military ceremonies, parts of the interior may be closed.

Who is it for? History lovers, photographers and anyone who wants to see Oslo from its old defensive walls. A walk around the fortress combines well with exploring the harbour and the city centre.