Going on a long trek is almost always special and unique (that’s one of the main reasons to go in the first place). The thing is though that you have to carry your own gear, so you have a vested interest in not taking too many souvenirs (except that additional water bottle I carried across the Alps).
Most (normal) people opt for the good old journal to record all the things happening and keep a memory of all the impressions (besides the GoPro and thousands of photos that you post on FaceBook or your blog gallery after).
Most European alpine huts accommodate for that and have stamps to put into your journal. On the more odd side of things… those stamps are not only available at every hut. 
There are quite a few peaks and saddles that have a little box attached to the cross on the summit that have either a log book and / or a stamp (and ink pad – old school) in it.
Now on a sunny summer day, this might be all easy peasy… when we hit the Friesenbergscharte at 2,910m it was incredibly windy (you could lean yourself against the wind and not fall over), starting to rain … and given you’re on a ridge line, where do you put your stuff – without it blowing away.
Here is my collection of stamps and other memories from trekking the #Traumpfad2015.
markus stanger 