Hovedøya Abbey

Hovedøya is one of several small islands off the coast of Oslo, Norway in the Oslofjord. The island is quite small, no more than 800 metres across in any direction, the total area is 0,4 square kilometre. It is well known for its lush and green nature, with a wide variety of trees, bushes and flowers. For many, many years there was a military base on the island.

The National Internment Camp for Women in Hovedøya (Norwegian: Statens interneringsleir for kvinner, Hovedøya) was Norway's largest internment camp for women, located on the island of Hovedøya in Oslo. It was used to detain women who had been accused of having romantic or sexual liaisons with German soldiers during World War II.

Akershus Fortress (Norwegian: Akershus Festning, pronounced [ɑkəʂˈhʉːs ˈfɛ̂sːtnɪŋ]) or Akershus Castle (Norwegian: Akershus slott [ɑkəʂˈhʉːs ˈslɔtː]) is a medieval castle in the Norwegian capital Oslo that was built to protect and provide a royal residence for the city. Since the Middle Ages the fortress has been the namesake and centre of the main fief and later main county of Akershus, which was originally one of Norway's four main regions and which included most of Eastern Norway. The fortress itself was located within the Akershus main county until 1919, and also within the smaller Akershus sub county until 1842. The castle has also been used as a military base, a prison and is currently the temporary office of the Prime minister of Norway.

Anatomigården is a historic house located on the north side of Christiania Torv in Oslo, Norway.

Norway's Resistance Museum also known as the Norwegian Home Front Museum (Norwegian: Norges Hjemmefrontmuseum) is a museum located at the Akershus Fortress in Oslo. The museum collection focuses on Norwegian resistance during the occupation of Norway by Nazi Germany from 1940 to 1945. The museum displays equipment, photos and documents from the war years.The museum was established as a foundation in 1966. The Museum was opened to the public in May 1970 by Crown Prince Harald of Norway in celebration of the 25th anniversary of Norwegian liberation. Architectural planning was entrusted to Norwegian architect Otto Torgersen (1910-2000) who working together with key personnel representing various branches of the underground forces, produced a chronological gallery through the period from the prelude in the 1930s onwards to liberation in 1945. The museum's first manager was Knut Haugland, who managed the museum until 1983. Tore Gjelsvik was chairman of the museum's council from 1964 to 1973. Arnfinn Moland was appointed manager of the museum in 1995.

Fortification Upgrades (1673–1675) was a re-organization of military forces and strengthening of the defenses of Norway. The Norwegian army in this period became much better prepared for conflict with Sweden than in any previous period. It numbered 12,000 men in five regiments of infantry, 6 companies of cavalry, and an artillery division with 76 field pieces. An additional Norwegian regiment was serving in Denmark. Ulrik Frederik Gyldenløve, Count of Laurvig was dispatched to Norway to evaluate the military forces in Norway. Gyldenløve was appointed Governor-general of Norway (Statholder) from January 1664 and commander-in-chief of the Norwegian army two years later. In 1673, Gyldenløve conducted a tour of facilities, after which he recommended upgrades to both the fortresses and the military forces. During the summer of 1675, 1800 men were kept at work on the fortresses at Akershus, Fredrikstad, and Fredriksten.

The Armed Forces Museum of Norway (Norwegian: Forsvarsmuseet - The Defence Museum) is located at Akershus Castle (Building 62) in Oslo, Norway. Previously it was named Hærmuseet, The Army Museum (even earlier the Artillery Museum), therefore, the museum consists of mostly army materiel. The Armed Forces Museum is the main museum sorting under the Norwegian Armed Forces Museum superstructure.

Pipervika is a neighborhood in the borough Sentrum in Oslo, Norway. It is located between the Oslofjord, Akershus Fortress and The City Hall Square. Today the term Pipervika is primarily used for the bay between the fortress and Aker Brygge. This was formerly commonly known as Piperviksbukta. It is part of the Fjord City urban renewal project.

Vippetangen is the southern tip of the Akersnes peninsula in central Oslo, Norway, located southeast of Akershus Fortress and bounded on three sides by the Oslofjord. It has in the past served as an important part of the port of Oslo. The area is currently undergoing urban renewal as part of the Fjord City development.

The Norwegian Military College (Norwegian: Den militære høyskole) was a military educational institution in Norway. It was established on 16 February 1817, with headquarters at Akershus Fortress. It was originally meant for artillery and engineer officers, but in 1826 it was expanded to include naval officers as well—however, not many naval officers actually attended.There were several changes in the length of the education offered at the Military College. From 1901 a two-year course was offered, educating personnel to the General Staff. The school had been mandatory for General Staff members since 1850. The school saw its demise in 1940, the same year as Norway was invaded and occupied by Germany.

The Vippetangen Line or the Grain Tram (Norwegian: Korntrikken) is an abandoned line of the Oslo Tramway, Norway, that ran from Tollbugata in the city center to Vippetangen between 1900 and 1967. It was built by Kristiania Kommunale Sporveie (KKS).

The Festning Tunnel (Norwegian: Festningstunnelen) is a motorway tunnel on European Route E18 in the city center of Oslo, Norway. The tunnel has two tubes, with three lanes in each. It runs from Bjørvika, under Akershus Fortress, The City Hall Square and Vika to Filipstad. The tunnel is 1,800 metres (5,900 ft) and −45 m (−148 ft) elevation at the deepest.The tunnel was previously also known as the Mountain Line (Fjellinjen) and the Oslo Tunnel (Oslotunnelen). The name Fjellinjen was since taken over by the company responsible for charging toll fees on the urban toll ring in Oslo. The tunnel changed its official name from the Oslo Tunnel to the Festning Tunnel in 1998 to avoid confusion with the railway tunnel with the same name. In 2008 and 2009, the electrical installation in the tunnel is being upgraded, financed through toll fees, costing 240 million kr. In the west, the tunnel connects to Dronning Mauds gate with a cloverleaf intersection, and also has the intersection prepared for a future Slottspark Tunnel. In the east, it connects to Nylandsveien and Ring 1 at Bjørvika. In 2012, the Bjørvika Tunnel will be constructed below Bjørvika, and the new tunnel will connect directly with the Festning Tunnel.The tunnel was built to remove traffic from The City Hall Square, the square in front of the Oslo City Hall, and allow better access to the waterfront from the city. After the tunnel opened in January 1990, cars remained on The City Hall Square until 1994. In 1995, the Vika Line of the Oslo Tramway was built across the square.