Cusco city in 1535. Remains of the palace of the Incas, Qurikancha (the Temple of the Sun) and the Temple of the Virgins of the Sun still stand. Inca buildings and foundations in some cases proved to be stronger than the foundations built in present-day Peru. Among the most noteworthy Spanish colonial buildings of the city is the Cathedral of Santo Domingo, Cusco. The major nearby Inca sites are Pachacuti's presumed winter home, Machu Picchu, which can be reached on foot by the Inca Trail to Machu Picchu or by train; and the "fortress" at Ollantaytambo. Less-visited ruins include: Incahuasi, the
Machu Picchu there is no evidence that Mach'ay was a burial ground. The central buildings use the classical Inca architectural style of polished dry-stone walls of regular shape. The Incas were masters of this technique, called ashlar, in which blocks of stone are cut to fit together tightly without mortar. The section of the mountain where Machu Picchu was built provided various challenges that the Incas solved with local materials. One issue was the seismic activity due to two fault lines. It made mortar and similar building methods nearly useless. Instead, the Inca mined stones from the quarry at the site, lined