We left Chile and entered Peru. The cities of Tacna, Arequipa and Puno are all desert cities.

The big challenges were the altitude changes, which are HUGE in Peru. Tacna is at sea level, but Atequipa is at 7661 feet ASL. We stayed a couple of days at Arequipa to try to adjust. But the next part of the journey still knocked us for a loop. The road to Puno, beside Lake Titicaca, passes over a mountain at 14800 feet ... higher than Mt. Whitney in California. Lake Titiis ar 12,300 feet, or close to this. But you cant avoid the climb to almost 15000 feet. Its a big change, another 7000 feet in altitude. It has taken us 3 days to try to recover from this.