 The actual location of the battle is the subject of some controversy . According to Canadian explorer John Hemming , Spanish forces occupied a plain between Ollantaytambo and the Urubamba River while the main Inca army was located on a citadel ( the Temple Hill ) overlooking the town , protected by seventeen terraces . However , Swiss architect Jean @-@ Pierre Protzen argues that the topography of the town and its surrounding area does not match contemporary descriptions of the battle . An anonymous account attributed to Diego de Silva claims that the Inca army occupied a set of eleven terraces , not seventeen ; while the chronicle of Pedro Pizarro describes a gate flanked by walls as the only way through the terraces . Protzen thinks that these descriptions allude to a set of eleven terraces that close the plain of Mascabamba , near Ollantaytambo , which include the heavily fortified gate of T <unk> . At this location , when the Spaniards faced the terraces they would have had the Urubamba River to their left and the steep hill of Cerro <unk> to their right , matching the three sides from which they were attacked during the battle . If Protzen 's hypothesis is correct , the river diverted to flood the battlefield was the Urubamba , and not its smaller affluent , the <unk> , which runs alongside the town of Ollantaytambo . 
