INKA ARCHITECTURE, Less is More--Much More!
Cyclopean stonework in the walls of the Sacsayhuaman Fortress
The essence of Inka architecture cannot be distilled into a single word. Three
themes demand recognition: precision, functionality, and austerity. The Inka
stonefitters worked stone with a precision unparalleled in human history;
their architects clearly esteemed functionality above decoration; yet their
constructions achieved breathtaking beauty through austerity of line and
juxtaposition of masses. The Inka seem to have presaged Mies Van der Rohe's
philosophy of "less is more".
The dominant stylistic form in Inka architecture is a simple, but elegantly
proportioned trapezoid, which serves the dual ends of functionality and
severely restrained decoration. Trapezoidal doorways, windows, and wall niches are found in Inka constructions
of all types, from the most finely wrought temples to crudely built walls in
unimportant buildings. The doorways and windows are obviously functional, and
the niches probably served a variety of functions as yet unidentified by the
archeologists. Placement of these trapezoidal openings was primarily
functional, but occasionally, esthetic
arrangements might dominate the placement of the trapezoids, if there was
no conflict with functionality.
Perhaps the single field in which the Inka builders allowed fancy to supercede
function is in their playful handling of flowing water. Sparkling streams
cascade from stone spouts, sometimes decorated
with carved designs, into joyfully splashing basins, then flow through
quite unnecessarily complex stone channels to pour into the next fountain (or
bath, as the fountains are sometimes referred to) and so on from fountain to
fountain, one after the other. The Inkas employed the sight and sound of water
as an element of architectural design and evidently enjoyed demonstrating their
mastery over the course of this essential fluid.
Various aspects of Inka architecture-- construction methods, design, and
characteristic features-- will be illustrated in the following paragraphs,
using photos taken in well-known archeological sites in the Cusco - Sacred
Valley - Machu Picchu area. No special archeological or architectural
expertise is claimed by the strictly amateur compiler of this webpage, just a
respectful awe of the achievements of these superb Andean architects and
engineers who left modern society these astounding monuments to enjoy and
Materials, stonecutting, and construction methods: Let us start by
looking at the working of the stone medium with which the Inkas built. They
built with locally available rock, from limestone to granite. However, the
"local" supply might be several kilometers distant and involve a transportation
problem that would have daunted a less capable people. At Ollantaytambo, huge
blocks were quarried from one side of the Urubamba Valley, shaped in part, and
then brought down the mountainside, across the Urubamba River, and up a long
construction ramp to the great fortress-temple complex above Ollantaytambo
The fortress-temple of Ollantaytambo is famous for its beautifully fitted great
slabs of red porphyry forming a portion of
what must have been intended to be its principal temple. But this complex, a
work in progress when the conquistadores arrived, was never finished.
A number of large cut blocks were abandoned en route to the site and remain
today, known as piedras cansadas or
"tired stones". Within the complex, a stone that was in the process of being
maneuvered into its final position can be seen lying on its
emplacement ramp. Other stones exhibit
peculiar grooves which were meant to be filled
with molten bronze or copper to lock two adjacent stones together (as was done
by the Greeks in their temple construction, and also by the people of Tiwanaku
near Lake Titikaka).
How the Inka cut stone without iron tools is not known with any certainty, but
in all likelihood stone was cut and shaped mainly with stone tools. Bronze or
copper tools may also have been used, but would be of limited use with the hard
varieties of igneous rock commonly used by the Inka. In Cusco can be seen an
interesting stone that was evidently abandoned while being cut in two; the
row of narrow holes forming the line along which
it was to be split seem to bespeak the use of a metal tool. Probably this
stone represents post-conquest work for the Spaniards. The
conquistadores admired Inka stonework sufficiently to employ Inka
stonecutters and techniques in colonial buildings, and many of the "ancient
Inka" walls in Cusco belong to the colonial period, such as this wall with
carved snakes and stones in non-Incaic shapes.
It is assumed the Inkas knew the technique of splitting rock using wooden
wedges placed in cracks, then soaked in water, until the expanding wood split
the rock-- a method developed independently by many ancient societies. The
quarries near Ollantaytambo were located in landslide talus, obviating the need
to detach the stone from the living bedrock. In any case, once split from the
bedrock, stones could be shaped by percussion using hammerstones. "Peck
marks" or, more properly, percussion marks
are obvious on much Inka stonework. Recent experiments have shown that stones
can be shaped with remarkable precision by using a series of increasingly
smaller hammerstones as the face is pounded into its final form.
The Inkas could also drill holes through rock, such as in this
ring of unknown function projecting from a wall
in Machu Picchu. Holes were probably drilled using grit and some sort of
pestle stone. Holes drilled through rock are narrowest in the middle and flare
outwards, as drilling with a pestle and grit would inevitably wallow out the
first-drilled portions of the hole.
But neither shaping stone into rectangular blocks nor drilling holes through
hard rock constitute reasons for the fame of the Inkas as the champion
stonecutters of human history. The glory of Inka stonecutting lies in their
ability to cut unusual shapes and fit them tightly together, as exemplified by
the famous "twelve-cornered stone" found in
a wall of the palace of the Inka Roca. It is both a cliché and a verity
that the stones are so closely fitted that a knife blade cannot be jammed
between them. How did they achieve these amazing close tolerances?
Scribing and coping: In 1987, architect Vincent R. Lee proposed that
the Inkas used a technique known as scribing and coping to fit their wonderful
jigsaw-puzzle stones. This technique is used to shape dove-tail joins of logs
at the corners of log cabins, resulting in logs carefully fitted together with
little or no gap between the cut log faces. A related technique could have
been used by the Inkas to shape their stones.
If the Inkas employed the scribing and coping method, the process might have
been something like this. To keep the illustration simple, we'll start with
a simple rectangular wall block that is to be set in a notch or seat carved in
the underlying wall stones or bedrock. A good example of rectangular blocks
set in bedrock notches can be seen in this foundation wall at Pisac. Our rectangular block has a bottom, top,
and two ends that must be fitted to their bedrock seat and the neighboring
stones in the wall. The front and back sides do not have to be shaped for any
particular fit. First the bottom and two ends are cut to a rectangular shape.
Next the seat and faces in the underlying stones must be cut to fit this block.
To do this, the block must be suspended above the stone on which it is to be
seated. For very heavy stones, this is not a trivial problem, but perhaps the
stone could be propped up by logs leaning in diagonally from the front and back
sides. Now, the cut outline of the suspended block is traced with a scribing
device on the stone below, into which a seating surface will now be cut out,
i.e., coped. The scribe could be a simple wooden triangular device, in which
one point is moved along the finished cut in the upper stone, and another point
shows where the stone surface below needs to be coped down to make the matching
face or seat. To achieve this, the angular relationship between the upper
stone and the lower stones must remain constant; this could be done through
the use of a plumb bob strung through the triangular scribe. Here is another
view of wall stones seated in carved-out notches, at Puca Pucara.
That the scribing and coping technique is a practical solution to the mystery
of the Inka stoneshaping methods was demonstrated by modern stonecutters under
the direction of Vincent Lee in the 1995 NOVA program "Inca". Whether or not
it was the technique used by the Inka may never be known, but no other
practical solution to the problem has been discovered.
Whatever the method used, it was a lot of work, even for the Inkas with their
great work force. As a result, a labor-saving device was commonly resorted to:
in much of the stonework, only the load-bearing surfaces are closely fitted
throughout the entire surfaces; vertical joins are commonly closely fitted
only to depths of a few centimeters from the outer face, with any leftover
space between the rest of the vertical joins being filled with sediment.
Inka walls: What the Inkas must have considered their very finest
stonework is found, naturally, in their most important buildings, their
temples. Temple walls are battered (inwards sloping), and constructed of
finely hewn ashlars laid in courses that
get progressively thinner upwards. This creates a wall with a wonderfully
stable and pleasing appearance, and which is, in fact, highly resistant to
seismic shaking. Earthquakes are a common building hazard in the Andean
region, and Inka stonework has survived for centuries, even as Spanish colonial
structures have collapsed. In fact, the most durable Spanish constructions
have been those that incorporated Inka walls. Here original Inka walls have been breached by Spanish colonial doorways;
note the inward slope of the lower wall, as opposed to the vertical upper wall
of European construction.
The inside face of these sloping walls is normally plumb, as seen here in the
fine stonework inside the Coricancha, the
Inka "holy of holies" in Cusco. Thus the walls were thicker at the base, where
the more massive courses were laid, and somewhat thinner higher up where the
courses were smaller.
A different style of wall construction is seen in some of the palaces built
for each Inka ruler-- the famed "cyclopean"
walls of oddly shaped blocks cut like jigsaw puzzle pieces and fitted
together to astounding precision with no mortar. Note the bosses on the stones in the previous picture; it is thought that
these might mark where logs supported the heavy stones while the seat was coped
into the underlying stones. In the case of the Sacsayhuaman fortress above
Cusco, cyclopean walls contain individual blocks estimated to weigh over 100
tons. Clearly there could be no repeated trial-and-error fitting of such
monster stones; they had to get it right the first time. Numerous large
stones in the fortress walls-- such as the stone above the model's head in the
next photo-- feature notches which may
indicate where the supporting logs were placed while the seat for the stone
was coped into proper shape.
Of course, not all Inka buildings were built of fine stonework. Buildings
of lesser importance might be constructed of rough stones set in mud, in a style known as pirca.
Inka doors and windows: As mentioned earlier, Inka doorways, windows,
and wall niches are trapezoidal. Some were simple, but elegant,
trapezoidal openings. The finest doorways,
called "double jamb doorways", have a recessed lip several inches wide inside
the outer trapezoid. This inner lip was, in most cases, a design element that
indicated an important doorway to a high status site. Such a jamb might also
have facilitated the emplacement of a wooden door to close the opening. That
doors were used to close some Inka doorways is indicated by a variety of carved
stone devices apparently used to hold a door in place. Simple stone rings carved in both sides of doorways
probably were used to tie a bar or other largely symbolic barrier in place, to
indicate a closed area. While no original wooden doors have survived the
nearly five centuries since the collapse of the Inka empire, elaborate closure
devices associated with numerous important entries and gateways appear to have
been used to hold real doors in place. One of the best examples, featuring a
stone loop above the doorway, and two barholds consisting of stone cylinders
fixed in niches on either side, is the principal
gateway at Machu Picchu. This portal opens through the main wall of the
Royal Estate, and clearly was meant to have a defensive door that could be
sealed in place with ropes, and braced, if need be, with heavy beams.
The sides of trapezoidal windows might be built up
with ashlars with one end cut to a gentle slant to conform with the
trapezoid sides, and capped by a long stone for a lintel. And they could be
framed with specially shaped stones cut and fitted "cyclopean style", as in the
case of the "Three-Windowed Temple" at Machu
Picchu. An unusual sight is the conversion of a trapezoidal doorway into a
window, as seen near the Intihuatana at Machu
Picchu. If you return to the image of the "Three Windowed Temple" (above), you
can see that it too was modified in this manner, having originally had five
windows. Equally interesting --almost startling-- is the modern use of the
trapezoidal doorway at Ollantaytambo.
Masmas or Wayronas: At Machu Picchu and other Inka
sites, buildings open on one side, known as masmas or wayronas,
are common. Lacking a wall on the open side, the roof had to be supported by
a beam stout enough to run the length of the building (or to a supporting
pillar in the center of the run). The notches in which the roof-supporting
beam was set can be seen in the end walls of this masma.
Roofing materials and techniques: Most Inka buildings were
rectangular, featuring steeply sloping gable
walls at the narrow ends, which served to support the roofing. Roofs were
thatched, over a framework of rafters and purlins running from a ridge pole at
the apex, down to the stone eaves walls (or support beam in the case of
masmas). Thatched roofs are common in Andean peasant dwellings today,
and the chroniclers of the conquest left no doubt that thatch was employed by
the Inkas on even their finest constructions.
Naturally, none of the original pole and thatch roofing has survived the
centuries at Machu Picchu, but a number of buildings have been
"restored", with roofs constructed in
much the same manner as sketched by Hiram Bingham, Machu Picchu's discoverer,
in his hypothetical reconstructions of Inka roofing. In these modern
restorations the roofing framework is lashed down to a series of tie-points
built into the walls. However, Vincent Lee has argued persuasively that the
roof-supporting framework was, in most cases, held down by its own weight, not
by being lashed to any built-in attachment points.
If Lee is correct, an alternative explanation is required for the stone pegs
and rings that are obviously attachment points associated with roof
construction in some way. The most visually obvious type of attachment points
are formed by stones carved with cylindrical bosses set into the gable walls to form a series of pegs
near the roof line. Less obvious, because they are normally recessed flush
with the sloping top of the gable walls, are stone tie rings, called "eye bonders" by Bingham. Lee has shown
that it is mechanically both unnecessary and impractical to use these tie
points to hold down the roof-supporting framework, except in particular Inka
buildings situated where strong updrafts are a problem (and in these cases
additional sets of pegs, recessed into the upper slopes of the gable walls
and apparently specifically created for the roof framework, were incorporated
into the design). According to Lee, the stone pegs are better explained as
tie points for lashing down the thatch itself, rather than the supporting
framework. The eye bonders are believed by Lee to have served to stretch
tight a closely-woven ceiling mat underneath the thatch. Such a ceiling mat
was reported in 1877 by archeologist-diplomat E. George Squier who described
in detail the roofing construction of an ancient Inka building which, in his
day, retained its roofing. The functional purpose of the ceiling mat would
have been to keep out vermin; in addition, such mats may well have served
esthetic purposes if woven with decorative patterns.
In Cusco, the Spanish chroniclers tell us the buildings were all flat roofed.
Here also wooden beam and thatch construction was used, which proved a
liability for the Spanish during Manco Inka's revolt against the
conquistadores in 1536, as flaming arrows torched the roofs of the
buildings in which the Spaniards were holed up.
Stairs and walkways: Considering the topography in which they built
their cities, it would be astounding if the Inkas were not master stairway
builders. Wide stairs marked the main "streets" linking the various levels of
their mountain towns, sometimes in long continuous flights made of
elongate stones laid flat to form each step.
In other instances each step consisted of a series of small stones, shaped and set in a row. And with surprising
frequency, the Inka resorted to the more laborious mode of stairway making,
hewing steps from the living bedrock.
Perhaps the most perfect example of steps carved from bedrock are those leading
up towards the "House of the Ñusta" at Machu Picchu:
six steps, curving slightly utilizing a bedrock
projection that otherwise would have been in the way.
On the other hand, access to work areas, especially agricultural terraces,
might be provided by narrow, steep steps or, more commonly, mere
stepping stones projecting from the terrace
Fountains and liturgical baths: As mentioned in the introduction, the
Inkas regularly manipulated the flow of water through their building sites via
canals and fountains. Though referred to by various authors as "baths" or
"liturgical baths", most of the fountains were just that, designed primarily
for the utilitarian, but essential, purpose of supplying potable water.
A few kilometers outside of Cusco is the archeological site of
Tambomachay, popularly known as the "Bath of
the Inka". This site consists of massive stone walls, at several levels, with
elegant niches, and a series of water fountains cascading from channels hidden
within the structure. The entire construction, or at least what remains today,
apparently was for the fountains themselves.
Water was brought through channels carved in the living stone, or through
conduits constructed of carved and carefully
fitted stones, such as those seen at Pisac.
A water supply channel might feed a single fountain such as the
Baño de la Ñusta in
Ollantaytambo. And fountains or baths were also arranged in long series, such
as at Phuyupatamarca, with six serial fountains; Machu Picchu, with 16
fountains, each different from the rest; and Wiñay Wayna, with a grand
total of 18 fountains, mostly identical in construction. A portion of the
Wiñay Wayna string of fountains can be seen at the
far end of the terraces at this magnificent
site. In close succession, one fountain feeds
At Machu Picchu, the uppermost fountain
is associated with important structures, and likely was truly a liturgical
fountain or bath. Obviously the water quality would be best in the uppermost
of the 16 fountains, and so it is assumed that this fountain served the more
important residents of Machu Picchu. Moreover, one wall of this fountain
enclosure features a small niche that an irreverent wag couldn't help but
compare to a soap dish! Notwithstanding the
obvious utilitarian value of a supply of running water to the residents of
Machu Picchu, this amazing series of 16 fountains is also art, with totally
unnecessary frills such as diverging and
re-joining water channels. The Inka stoneworkers played with the water
right on down to the lowermost fountain's zig-zag feed channel.
Agricultural architecture: Probably the most ambitious constructions
undertaken by the Inkas, certainly in terms of volume of material moved, are
the innumerable sets of agricultural terraces built on mountainsides and in
river bottoms throughout the Inka empire. Known as andenes, terraces
were formed with stone retaining walls, holding in a lower layer of coarse
rubble (to ensure proper drainage), and an upper layer of good topsoil (which
in some localities had to be carried long distances up the mountain from the
valley below). Spectacular terraces at Pisac are still cultivated today. The individual terraces are
accessed by stepping stones tenoned into the
terrace walls. At Machu Picchu, the "agricultural sector", devoted to
andenes makes up approximately half the site and likely could have
produced more foodstuffs than required by the estimated 300 permanent
inhabitants of the Royal Estate.
Although quite capable of transforming steep mountainsides into agricultural
lands, the Inkas naturally preferred the rich valley bottoms. Fertile valley
bottomlands were terraced and riverbanks walled to protect these richest lands
from erosion. The Sacred Valley of the Urubamba River was under intense
agricultural use in Inka times, as it is today. To protect choice agricultural
land near Pisac, the Urubamba was canalized
for at least 3.3 km, said to be the largest pre-Columbian canal project in the
Architectural legacy: The Inka civilization has left the world, and
Peruvians in particular, with an immense architectural legacy. Machu Picchu is
certainly one of the most famous archeological sites in the world, and a visit
there can be a mystic experience. Hiking still-intact portions of the vast
Inka highway systems is a wonderful experience for outdoor adventurers. A
tourist industry based on Inkaic works is important to modern Peru's economy.
But the Inka legacy extends beyond mere tourist attractions. A remarkable
portion of what they built is still in use: Inka walls still support the most
important buildings in Cusco, surviving earthquakes that send more recent
constructions toppling to the ground; 500-year old andenes still grow
food for Peruvians. Studies of agricultural works-- Inka terraces, the
camellones (raised agricultural beds in flood-irrigated lands) found in
the Lake Titikaka area, and complex irrigation canals constructed by
pre-Columbian cultures on the Peruvian coast-- may lead to improvements in
modern land usage patterns and increased output of foodstuffs in Peru.
These ancient works of lasting usefulness are sources of national pride to
Peruvians, and perhaps someday will play a role in a renaissance of indigenous
culture in Andean Peru.
Much information about Inka architecture was taken from "Monuments of the
Incas" by John Hemmings and Edward Ranney (1982), a fine scholarly work
The author of this webpage is also indebted to Peter Frost's very excellent
guide to the Cusco area, "Exploring Cusco". No visitor to the Cusco region
should be without this fine guide, available in inexpensive paperback, and a
terrific compendium of information, well presented.
By far and away the best guidebook for Machu Picchu is "The Machu Picchu
Guidebook -- A Self-Guided Tour" by Ruth M. Wright and Alfredo Valencia Zegarra
(2001, 2004). This webpage has benefitted materially from information in this
guidebook and a series of papers authored by Kenneth R. Wright.
Vincent R. Lee's scribing and coping theory of stonecutting is presented in
detail in his article "The Building of the Sacsayhuaman", which was published
in 1990, vol. 24 of Nawpa Pacha, the journal of the Institute of Andean
Studies. His theory on Inka roofing techniques is described in his paper "The
Lost Half of Inca Architecture", presented in 1988 at the annual meeting of the
Institute of Andean Studies. These articles, and related writings, are
available in reprint form directly from Lee, who can be contacted through the
WWW: search on "Sixpac Manco"!
Ephraim George Squier's beautiful book, "PERU: Incidents of Travel and
Exploration in the Land of the Incas" was published in 1877 by Harper &
Brothers and is now a sought-after collector's item; even a modern facsimile
edition is now scarce. This 599-page work, illustrated with abundant
engravings, is a wonderful combination of pioneering archeological work and
descriptions of the marvellous adventures inherent in 19th-century travel
across the Andes.
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Photos on this website by Janie and Ric Finch, @copyrighted.