Oslo is the capital of Norway and the largest city of the country. However, it is large only for Norway standards, the population is about 600 thousand people. It's curious that from 1624 to 1924 it was called Christiania.
The city center is quite compact and you almost do not need public transport to see the most interesting places.
You should start from the City Hall, which is located in the harbor. If you stand back to it, then to the left will be the Akershus Fortress of the XIII century. It is possible to walk along the walls and admire a great view of the harbor.
To the right is the Aker Brygge district. It is the most visited place in Norway, every year more than 12 million people walk here. Until 1982, shipyards and industrial buildings used to be here. The first phase of construction of modern residential buildings was completed in 1986. Since then, the district has been gradually expanded and turned into a holiday destination for millions of tourists who like to stroll along the waterfront and sit in the restaurants. The distinctive features of the district are unusual architecture and street design.
One of the main attractions of Oslo is the Opera House, which was opened in 2008. Its distinguishing feature is the roof. The roof of the building angles to ground level creating a large plaza that invites the pedestrians to walk up and enjoy the panoramic views of Oslo.
You will need public transport to visit the Vigeland Sculpture Park. Use the bus #20 or tram #12 as well as all subway lines to the Majorstuen station. However, the park is located within walking distance from the downtown, just 3 km.
It's quite hard to describe the park, this is definitely a "must-see" place :)
You will also need public transport to visit the Viking Ship Museum, which is located on the Bygdoy Peninsula (map). Besides various stuff of the Vikings, you will find here the two best-preserved ships of the 9th century.
It's easy to get to the museum by bus #30 from the Nationaltheateret stop (National Museum of Art, located behind the City Hall) to the Vikingskipshuset stop. From April to October you can use a ship from the Rådhuskaia pier (near the City Hall) to Dronningen.
There are two more marine museums nearby. The Fram Museum is dedicated to three outstanding polar expeditions that took place on board the "Fram." The ship itself is also in the museum. The Kon-Tiki Museum is dedicated to the life and work of Thor Heyerdahl. The main exhibit is the Kon-Tiki raft, on which the famous Norwegian crossed the Pacific Ocean in 1947.
1. The Oslo Airport Gardermoen is located 45 km away. The city can be reached by the Flytoget Airport Express Train ($42). There are also several NSB trains, which are much cheaper ($15, schedule). You can also take the Flybussen bus ($26, price, schedule).
2. The Torp Sandefjord Airport is located 110 km away. The city can be reached by the Torp-Ekspressen Airport Bus ($40, price, schedule) or by NSB train from the Sandefjord Airport Torp station ($40, schedule), there's a free shuttle bus to the station from the terminal.
3. The Moss Airport Rygge is located 66 km away. The city can be reached by NSB train ($25, schedule) and also by the Rygge-Ekspressen Bus Service ($17, price, schedule).
Here are details about the ferry lines that connect Oslo with other countries, mainly with Denmark, Sweden, and Germany.