Our evening culminated with a trip to Sacsayhuaman, the Inca fortress overlooking Cusco. Historically, Sacsayhuaman was a part of Cusco. The Incas built the city in the shape of a puma, with Sacsayhuaman representing its head. Sacsayhuaman exemplified the skill of Inca stonemasons. As the conquistadors once remarked, you can't wedge a knife in its crevices. Many of the stones were about my height, which begged the question: "How did y'all do this?"