Summer and early fall
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Once you get up to the second plateau you can wander to your heart's content through beautiful meadows. The larches are particularly beautiful in the fall.
@Micha: Map, length etc here :) https://www.trails.com/tcatalog_...
Also seems that it's closed December 1st to June 15th. @Kim: How about a hike in late October - November? Possible or too difficult because of the snow?
Beautiful larches! I'd go in fall as well.