Peru
The places in your article on Peru are great but the one thing not mentioned is the altitude and the fact if you fly into Cusco and move too fast when you get off the plane you could easily collapse!
I recommend taking a pair of flip flops or sandals to wear after your day of trekking - it's far more pleasant than keeping your sweaty boots on! Additionally, take more money than you think you'll need, as there is water and beer to be bought en route, and you'll want to be generous with your tips for the porters and guides.
At that altitude, you may need the local brew, and not Cusquena!
Eating small meals and drinking little alcohol will help too - I learned the latter the hard way.
everywhere
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