The highlight of the trip to Peru was the trek to Machu Picchu (well, not Machu Picchu specifically, to Aguas Calientes - the town from which one visits the archeological wonder). My brother, his fiancée, another traveling companion, and I traveled with Salkantay Trekking. The word "gueling" appeared next to almost any mention of the Salkantay Trek - a five day, four night hike up through the Salkantay Pass and back down again. The first day, after lunch, they take you up a sheer rocky hill to a glacial lake at the base of the Humantay mountains. The unreal aquamarine tones of the lake reflect the towering mountains, covered still in ancient blue snow.