Great question — answering as the UphillTech team:
I have hiked the entirety of the Kungsleden, did an 11 day Sarek crossing and have also been on parts of the Nordkalottleden and the Padjelantaleden - so you could say I am fairly experienced with northern Scandinavian mountain treks. Kungsleden I did Kungsleden in 2006 - 'crowded' meant for us that we maybe saw some 5 groups of people per day, sharing camp grounds around the huts with maybe some 5 parties each night. That was on the northernmost section (Abisko southwards), which is also the most popular one. In 2018 I was again hiking parts of the northernmost Kungsleden sections, we met maybe 10-20 parties per day, with some avg. of maybe 10-30 people camping at the huts. If you go...
Full answer by fgysin: https://outdoors.stackexchange.com/a/15114 (CC BY-SA 4.0).
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