When Oslo was named capital of Norway in 1299, King Håkon V ordered the construction of Akershus, strategically located on the eastern side of the harbour, to protect the city from external threats. Extended and modified over the centuries, it still dominates the Oslo harbourfront and the sprawling complex consists of a medieval castle, Akershus Slott (currently closed for renovations), a fortress and assorted other buildings, including still-active military installations.

　　Entry is through a gate at the end of Akersgata or over a drawbridge spanning Kongens gate at the southern end of Kirkegata. After 6pm in winter, use the Kirkegata entrance.

　　The Akershus Fortress Visitor Centre, inside the main gate, has permanent exhibits recounting the history of the complex, as well as temporary exhibits highlighting aspects of Oslo's history. Staff can organise guided tours. The fortress also serves as the backdrop for a raft of cultural events throughout the year, from theatre performances to music recitals. Check the website for listings.