The main drag from Oslo station is called Karl Johans Gate.
There are cafes and shops inset into the old cathedral. If
you wander (far) off the beaten track, you can find some interesting buildings around and about.
The Viking Ships museum has some excavated stuff, in amazingly good condition thanks to clay burial mounds. The highlights are a luxury ship and a war ship. There are even some preserved fabrics, carvings, etc.
The Kon-Tiki museum was fascinating. It explains the experimental voyages of
Thor Heyerdahl. He demonstrated the possibility of pre-colonial contact
across oceans, using rafts built with traditional materials and
techniques. The Kon-Tiki balsa-wood
raft made it from Peru to Polynesia. The Ra II papyrus raft made it from
Egypt to South America (the first one sank). There are many parallels
between the disparate cultures, of which these statues are one small
example. He also did some interesting experimental work on Easter
Island.
On a random wander I came to a forest reserve, and walked for an
hour or two in it. The forest is surprisingly rich. At one point, I went off the path a while in
search of a view, and came across this wigwam... your guess is as
good as mine. I eventually found the view I'd been looking for, over
the Oslofjord. Also looking inland.
Town Hall
(Rådhus)... One of the labourers
who built the thing. Fresco
depicting resistance during WW-II occupation...
etc.
He was arguably a bit
disturbed, perhaps partly due to his father. Who knows?