We decided to stay at the Hotel Pakaritampu which is a 3-star hotel conveniently located near Ollantaytambo ruins, with quick access to the train station. Because Ollantaytambo is 1,000m (3281ft) below Cusco (which is 3,400m or 11155ft above sea level), it provides a very good location to begin the acclimatisation process. In fact many visitors to the region travel directly to the Sacred Valley after landing in Cusco to reduce the likelihood of experiencing altitude sickness. We stayed in Ollantaytambo for two days to acclimate and to enjoy the the nearby Inca ruins. In the process we got to know the truly beautiful and historic town of Ollantaytambo.
At the Larco museum in Peru, they had a collection of the most unusual cacti I have ever seen. Earlier in cactus taxonomy, Cereus was a name that had been applied to nearly all known cactus species that were ribbed, columnar plants. Many of these plants have since been moved out into separate genera. Consequently, the 30 or so plants that remain in the Cereus group are largely plants that have not been moved out of the genus rather than plants that have been included because they fit the description of Cereus. This inclusion-by-lack-of-exclusion makes for a very messy and unsatisfactory grouping. The name Cereus peruvianus has been applied to both C. hildmannianus and C. repandus which are both recognized as legitimate species today. The trouble is, neither of them resemble the many plants that we see labeled as Cereus peruvianus.