Take the overnight ferry and go straight to Bergen as Oslo is a bit bland.
Then go from there into Sweden.
Enjoy the History Museum gold hoard, the City Hall with its very scenic park and views of the bay, Nordiska Muséet and Skansen in the Swedish capital. Walk the medieval alleys of Gamla Stan and see the worth-wile world-class grandeur of the interiors of the royal castle, which are truly opulent and surprisingly varied (1740-). You could mount a bed in those colossal Parisian chandeliers. Take bus 403 to the terminal stop Östervägen (19 min), alt. bus 401 to Hellasgården, for the Källtorpssjön nature reserve trails by the jetty, and swim in the lake. Take Saltsjöbanan to the seaside beach at Erstaviken. Look up Årsta Havsbad to see if you would like to swim at this seaside Lord of the Rings panorama.
Day trip to Uppsala for the large cathedral, the splendidly situated castle, several botanical gardens that range from quaint to magnificent, and the viking heartland of Gamla Uppsala, where the giant burial mounds will move you back to a time before Christianity. They are Scandinavias frosty reply to the pyramids at Gizeh.
The bread and the pastries are the best and most varied in the world, and you should go to great lengths to sample all the varieties. Purchase kavring, rågkaka and tunnbröd at a good bakery (or even at a supermarket) and get to know a few of the hidden wonders of the northern cuisine. Have fika with cinnamon buns, cardamom buns, sticky chocolate cake, 3 varieties of sponge cake, and a minimum of 5 kinds of biscuit at a confectionery; Güntherska and Landings in Uppsala, Vetekatten, Rosendals Trädgårdar and Grillska Huset in the capital, Taxinge Slottscafé (with a giant-size pastry selection) in Mariefred. Pastries and bread are one of the few things that are a cultural constant, and the bread you choose would easily have been recognized by people, in one region or another, who lived 100 years ago. SPECIAL RECOMMENDATION: The singular Skansen heritage (1870) bakery! All you want is all they've got!!!