The trek was amazing - difficult, but beautiful. The high altitude was intense, but it can definitely be done. Our guide Victor was great and made the trip a lot of fun! We also had a great group with unique and interesting people.
My favorite part of the trek was Humantay Lake which was an incredible sight - the lake meets the mountains and the glaciers reflect off the water. It's a long walk up to it though - well worth it! Aguas Calientes is a cute little town and it was a great stop the night before seeing Machu Picchu.