Hey Bryon,
the best levels you will find in late May. But in June it's still good and I think nearly all standard section will be runable.
From Oslo it's a short trip to the
Telemark. Good rivers are:
-
Mar
(Homerun) - a WW IV classic run of 500m of finest drop'n'pool
-
Tessungselva/Austabygdai
- WW IV-VI run, depends on the level. Many more or less huge drops
-
Goyst
- WW IV-V with many really cool slides
-
Skoogsaa
- WW IV (- V,VI,X) nice river with many slides and "warm" water
The next destination should be one of the classic whitewater areas in Norway, the
Sjoa area.
-
Sjoa
- WW III-VI (X) the Sjoa has many sections which are all runable, esp. Ridderspranget should be mentioned...it is completly runnable! ...but not for everyone
Good sections to get in touch with big water is the Playrun. A nice gorge is the Asengjuvet section, but be careful there is one hole in this section on the left side of the river which you won't compete...even if you are swimming. Another cool section is the Amot, directly after the Playrun. Esp at high levels it is a challanging ride. A narrow gorge with brown water at high levels and many nasty eddylines...better don't swim in this section.
-
Frya
- WWIV we didn't run this section because we had twice the water we should have
but from scouting at a bridge I can remember a tricky combo of a drop and a hole in a right bend...if the drop messes you up you will swim the 6m drop 
-
Lagen
- WWIV - V
Region Otta
- Otta - WW IV-V (VI) Pollfossen run depends absolutely on the level...I think you can run it between 90 and 500 cbm...at 500 just partially

-
Store Ula
- WW IV-VI+ (X) this is a must run, starting at a parking lot of Rondane National Park you have to hike 10 minuetes to the put-in. You will find great slides in an unbelieveable nature...just do it! The big slide...you will know what I mean...is not that fast as it looks. It's well controlable
Okay that's it, I think in one week starting in Oslo there no need to go northerly than Sjoa/Otta.
On the way fron Mar to Sjoa you might take the Numedalslågen, a great bigwater run between 100 and 500cbm

(stay absolutly right in the broken weir at the end

)
Cheers
Max
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