I used to carry 70 lb in the mountains when I was young (at Uni). I needed help to stand up, but then I was OK. Today, at 74, I definitely do NOT want to carry that much!
But the long length of the trip – too right. We (Sue & I) have done many 2-month trips on the tracks in Europe, and one 3-month trip. Coming home is always a bit of a psychological let-down.
https://backpackinglight.com/caffins_4_month_gear_list/
https://backpackinglight.com/caffin_gear_list_revisited/
However, in Europe we had the chance to buy food as we went. Fresh French bread and cheese – oh yeah! Even, sometimes, red wine …
Cheers

