Inca Buildings and Inca Architecture

Incan architecture is the most significant pre-Columbian architecture in South America.The Incas inherited an architectural legacy from Tiwanaku, founded in the 2nd century BC in present day Bolivia.
The capital of the Inca empire, Cuzco, still contains many fine examples of Inca architecture, although many walls of Inca masonry have been incorporated into Spanish Colonial structures. The famous royal estate of Machu Picchu is a surviving example of Inca architecture. Other significant sites include Sacsayhuaman and Ollantaytambo. The Incas also developed an extensive road system spanning most of the western length of the continent.

Water engineer Ken Wright estimates that 60 percent of the Inca construction effort was underground. The Inca built their cities with locally available materials, usually including limestone or granite. To cut these hard rocks the Inca used stone, bronze or copper tools, usually splitting the stones along the natural fracture lines. Without the wheel the stones were rolled up wood beams on earth ramps. Extraordinary manpower would have been necessary. Hyslop comments that the “ ‘secret’ to the production of fine Inca masonry…was the social organization necessary to maintain the great numbers of people creating such energy-consuming monuments.”

Usually the walls of Incan buildings were slightly inclined inside and the corners were rounded. This, in combination with masonry thoroughness, led Incan buildings to have a peerless seismic resistance thanks to high static and dynamic steadiness, absence of resonant frequencies and stress concentration points. During an earthquake with a small or moderate magnitude, masonry was stable, and during a strong earthquake stone blocks were “ dancing ” near their normal positions and lay down exactly in right order after an earthquake.

Another building method was called “pillow-faced” architecture. Pillow faced building was achieved by using fired adobe bricks and mud mortar. The Incas would then sand large, finely shaped stones coated in mud and clay. Then they would fit the bricks and stones together using the mud mortar into jigsaw like patterns. Pillow-faced architecture was typically used for temples and royal places like Machu Picchu.