Hello, From the Gardermoen airport the the quickest way into central Oslo is the airport express train. It leaves every 15 minutes, costs NOK 170 one way (yes expensive!) but takes just 23 minutes into the Central Station. From the Central Station you can take tram line no. 12, that says Kjelsås on the front, heading north. You can get off at Birkelunden stop and walk down through all the area, exploring the other squares and side streets. Be sure to buy a ticket in advance before getting on the tram - the best thing to is buy a day pass, then you can travel on all trams, busses and the subway for 24 hours. If you want to go to the Vigeland sculpture park from Grunerløkka the quickest way to get there is this: Get back on the 12 tram going to Kjelsås, as the driver to tell you the stop called Torshov. Get off here, cross the street to the 7-11 store on the right hand corner of the crossroads. Here you can find the bus stop for bus 20 to Skøyen. This bus drives then drives through a few nice areas of Oslo directly to the Vigeland sculpture park and stops outside the main entrance gates. Be sure to scan/validate your day ticket card when getting on to the tram or bus, this is the same as the Oyster card system used in London :-) Fines for travelling without a valid ticket are NOK 900,- so a day card is a good investment, just be sure to validate it! :-)