Akershus Castle and Fortress is a medieval complex that was built to protect Oslo. It has also been used as a prison. The main building now is used for official events and dinners for the foreign heads of state. Akershus fortress is still a military area, but is open to the public daily until 21:00.

Oslo's National Theatre was inaugurated in 1899. The building is designed by architect Henrik Bull, and has served Norway's main arena for stage artists, theatre productions and large celebrations for over 100 years. Statues of the great Norwegian writers Henrik Ibsen and Bjørnstjerne Bjørnson guard the theater's main entrance. They also have their names engraved on the theater's facade, along with the Dano-Norwegian playwright Ludvig Holberg.

Built in 1866, Norway's yellow-brick parliament building is one of Europe's more charming parliaments. If you find yourself really hooked on Norwegian political debate, you can tune into the live action through the Stortinget website.

Oslo cathedral is a very old church, dating to the 17th century. The Norwegian Royal Family and the Norwegian Government use the Cathedral for public events. In 2001, Oslo Cathedral was the site of the wedding of Haakon, Crown Prince of Norway, and Mette-Marit Tjessem Høiby.

The Royal Palace was constructed for the new French-born king of unified Norway and Sweden. It has been the official royal residence since then. The palace is open for visitors with the advance appointment late June to mid August. The beautiful baroque park of the palace is open for visitors every day.

Holmenkollbakken is a large ski jumping hill located at Holmenkollen. It's a large hill with the capacity for 70,000 spectators, requiring the special permit for athletes to use. Holmenkollen has hosted the Holmenkollen Ski Festival since 1892. It's also a cross-country and biathlon venue. Holmenkollbakken is co-located with Holmenkollen Ski Museum, which presents the history of skiing.