Hello !
Grossglockner, Stelvio, Bonette, Alpe d'Huez, Ventoux, Mortirolo, Monte Grappa, Pico Veleta and Roque de los Muchachos (La Palma, - Canary islands) should be sure in the TOP 10 and... the following:
Based on the data of salite.ch and climbbybike.com (the 2 most important climbs' profile database) the climb to
Grosser Oscheniksee (2394 m) is the hardest or 2nd hardest paved ascents of the Alps, harder than the Monte Zoncolan or Angliru in Spain.
Data: 17 km & 9,8%, but the last 10 kms = 13% steepness, but often 14-15% and max. 18-20% (you can see it in my video )
That's an epic, a monster, a killer, but I loved it. That was a real challenge !
That's
my detailed video about it (I edited that this week) - with english subtitles :
https://www.youtube.com/watch?v=6C70JluUdLg
two pics about the upper part:
Bst regards,
Gabor
and: