The Inca Trail took four days to hike, but day 2 was the killer day. I think our base camp was about 9500 feet and we hiked at a 30 to 45 degree angle for about five hours! We topped out at 14,000+ feet. That’s the highest elevation I’ve ever been at. Our guides actually brought oxygen tanks and if they were offering I was taking! Knocked out my headache in about two minutes! The hike was 47 kilometers but the thing that made it so challenging was the radical challenges in elevation. My legs were screaming by Day 4.