The 90km of asphalt at Klarälvsbanan (the Klarälven trail), where traffic is prohibited, is perfect for inline skating. From Karlstad, through Klarälvdalen and up to Hagfors, you can travel on the old disused railway embankment, all of which is now coated with asphalt. You will travel through Värmland's wonderful landscape on smooth asphalt and Klarälven will be in close proximity throughout your journey.
There are several beautiful areas along the trail where you can relax and rest. Furthermore, there are many toilets along the route for your convenience. Inline skating is a great total body workout and it does not strain your knees. Of course you should always wear a helmet as well as wrist, knee and elbow pads for protection.