Infamously, THE HARDEST DAY!
And it is, hard. 98 percent uphill followed by a slippery, rainy descent into camp. Your legs will be screaming. But looking back, it's hard to get back into the mindset of how hard it was - all I feel is pride and relief at having accomplished it. I honestly feel like I could do anything now.
Colca was great preparation - and again, I killed Walker on the uphill. The guy loves to take breaks. Occasionally on this day there would be ladies selling Gatorade along the trail and I almost lost Walker to them.
One of the hardest parts of the trail is the constant fluctuation in body temperature. The shedding of layers, only to add them back when your sweat cools.
We also went during rainy season (it means the trail is not overcrowded, but it also means a lot of rain (duh)) which required putting on the rain gear and peeling it off every ten minutes.
The real miracle of the entire trail (and the real motivators) are the porters. There are about 18 or 19 per group that carry the tents, cookware, etc. (you carry your own personal stuff) - they've been doing this for centuries: tiny, compact bodies and in the sandals they prefer over hiking boots. They literally zoom past you on the trail going straight up a mountain with 30lbs on their back like it's nothing.
There's definitely a history of mistreatment which can make you feel pretty skeevy, but laws now limit the amount they can carry, require them to take breaks, be provided with food, etc.
You also individually tip them at the end with a sort of appreciation ceremony.