During my journey through Norway at the end of August I'll have a 4 hour layover in Oslo. My train arrives on 07:04 at Oslo sentralstasjon and the train departs on 11:01 from the same station. This is on a Tuesday.
I've never been to Oslo before and was wondering if I could do some sightseeing in this short time. I'll probably leave my luggage in the lockers so I'll have more mobility.
I would want to avoid using public transport for more than a few stops as that might result in a delay and missing my train, so preferably the sights should be within 1 hour walking distance of the train station.
Shops/malls and the like are mostly the same across Europe so I am not interested in those.
I am interested in historical sites and buildings that can be found in Oslo. Also a nice quiet vantage point from which I can overlook the city and eat some breakfast would be fantastic, but I'm not sure if that exists.