Who would know?
Cicerone guidebook author Kev Reynolds:
The general consensus of opinion usually names the GR20 high-level route across Corsica as the toughest of the Grande Randonees (SP), but with some justification the Pyranean Haute Route – which teeters across the frontiers of France and Spain – gathers a lot of votes.
Both are long and demanding, have sections without proper paths, and journey through remote country, often far from habitation.
Yet there’s another long and challenging route that is also a contender for the title …
The Tour of the Oisans, also known as GR54 …
All 3 sound great to me.
These are routes that have guidebooks and maps. Not off trail adventures.
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