Bleikøya

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.

Gressholmen is an islet located in the Oslofjord, just south of central Oslo. Administratively it belongs to the borough of Gamle Oslo. Gressholmen airport was for the years 1927 through 1939 the location of the main airport for Oslo, until the construction of Fornebu airport. The airport was only for seaplanes. The ramp with rail tracks and the hangar are reused for boat storage and maintenance. There is railway point with the big track gauge. The island is easily accessible from Oslo with the local ferries. The access point is on the North side. A big part of the island is a nature reserve.

Bunnefjorden, sometimes referred to as Bunne Fjord, is a part of the Oslofjord in south eastern Norway, located east of the Nesodden peninsula. The Bunne Fjord is flanked by the municipalities of Oslo in the north east, Nordre Follo to the east, Ås to the south east, Frogn to the south west, and Nesodden to the west. The Bunne Fjord has a very long water residence time, and the water is of poor quality. The significant islands in the Bunne Fjord are Langøyene, Malmøya, Ulvøya, Ormøya, Gressholmen, and Husbergøya.

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.

Hovedøya Abbey (Hovedøya kloster) was a medieval era Cistercian monastery on the island of Hovedøya in Oslofjord outside of Oslo, Norway.

Gressholmen Airport (Norwegian: Gressholmen sjøflyhavn) was a water aerodrome situated the island of Gressholmen in Oslo, Norway. It served as the main airport for Oslo from 1927 to 1939, along with Kjeller Airport. The aerodrome consisted of docks, a landing ramp, terminal building and a hangar and used a section of the Oslofjord as its runway. Being located on an island it was necessary to transport passengers by boat to the island. The airport only operated during the summer, typically from May through September. Oslo's first airport was located on the neighboring island of Lindøya, but the authorities preferred Gressholmen as a location. Although plans surfaced in 1919, funding was not ensured until 1926. Norsk Luftruter received a concession to operate the airport, ground handling and the ferry service. Deutsche Luft Hansa commenced the first service on 18 July 1927, flying from Oslo via Gothenburg and Copenhagen to Szczecin. The following year the terminus was moved to Travemünde outside Lübeck. The airport was also used by Halle & Peterson's Norway Post flights during the early 1930s and by Widerøe in 1934. Norwegian Air Lines (DNL) started domestic flights and an international service to Amsterdam in 1935. Deutsche Luft Hansa moved its flights to Kjeller from 1938 and from 1 July the following year all civilian traffic was transferred to Oslo Airport, Fornebu. Gressholmen saw a limited amount of use by the Royal Norwegian Navy Air Service, the Luftwaffe and the Royal Norwegian Air Force until it was closed in 1946. Most of the facilities, including the hangar, remain today and are used for a marina.

Langøyene is an island in Bunnefjorden in the inner part of Oslofjord, in the municipitality of Nesodden in Akershus, Norway. It is owned by the municipality of Oslo. Langøyene were originally two islands, Nordre Langøy and Søndre Langøy. The islands were bought by the municipitality of Kristiania in 1902, and the strait between the two islands has been filled with garbage deposits.

Heggholmen Lighthouse (Norwegian: Heggholmen fyr) is a coastal lighthouse located in the Oslofjord, in the municipality of Oslo, Norway. It was established in 1827, and automated in 1972. The lighthouse was listed as a protected site in 1998.

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 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).

Malmøykalven is an island in the Oslofjord in Oslo, Norway. It has an area of 98,000 m2, and is located west of the island of Malmøya, separated from Malmøya by a narrow strait. Malmøykalven is included in the Malmøya og Malmøykalven Nature Reserve, which was established in 2008.

The Sjursøya train accident was a railway accident that occurred on 24 March 2010 at around 13:15 local time, when a set of 16 freight cars began to roll uncontrollably during shunting on Alnabru, north in Oslo. The train dispatcher central chose to lead the runaway train in the direction of Sjursøya, along the Loenga–Alnabru Line, where it derailed and rolled through a Statoil building in the terminal area at Sjursøya, a peninsula which is part of the Oslo ports facilities. The line leading to the container and petroleum port at Sjursøya is a branch of Østfold Line, and is only used at low speeds. However, the empty carriages crashed into the harbour terminal at an estimated speed of more than 100 km/h (62 mph). At the most, the set of wagons had a speed of 90–140 km/h.According to police reports, three people were killed in the accident while four people were injured. Of these four, three were severely hurt and the fourth person received minor injuries. According to TV 2 Nyhetskanalen, the condition of three of the injured persons was critical.