The only way is up.
Arica - La Paz
The coach from Arica to La Paz (CALI) was old and less comfortable than normal long distance coaches in Chile. It had a toilet (unlike all other coaches in Bolivia), and they served a more home cooked style meal in aluminum take away containers, rather than the common (in Chile) plastic wrapped, ready made food - the food was rice and vegetables and some chopped sausage - I hadn't expected there to be any food and didn't accept any food anyway (as usual) - just saying it wasn't a bad meal, except for the mixed in, theoretically hard to pick out, greasy dead person sausage. Maybe one day they'll switch to vegan sausages.
and altitude sickness
I chewed some coca leaves. But this made me feel a little bit sicker, I think. Also I thought (after chewing the leaves), I probably shouldn't just chew some unwashed dirty leaves in Bolivia. It left me with a profound aversion to the smell of coca leaves for the rest of the Bolivia trip - and in Bolivia everything smells like coca leaves.
I should have just drunk the mate de coca (coca leaf tea) - served in plastic bags with a straw.
If you could see things from my vantage point...
You'll also see many llamas and alpacas, and maybe vicuñas and donkeys.
the Chilean Hampi