Construction Theories
In the Sacred Valley at the site of Ollantaytambo lie many unfinished blocks of ryholite. They were quarried or collected from a large rockfall 2.17 miles away across the Urubamba River. How are the massive stones quarried, transported, dressed and placed? The lack of written history leaves it up to us to figure out by observation, comparison, and experimentation.
Quarrying did not occur in the classic sense of hewing raw blocks from solid cliffs. The Inca stonemasons searched the rockslides for blocks that would suit their purposes. Often the raw blocks were partially shaped at the quarry or during transportation. Final fitting and dressing of the stones occurred at the work site.
Rough shaping of stones was accomplished by two main techniques. At the base of the ramp leading up to the Sun Temple at Ollantaytambo lie several blocks abandoned in transit. One shows small holes pecked into a natural groove into which wedges were driven to split the stone.

The other method for roughing stones was to simply carve a collar around the stone until the unwanted portion broke off. This worked on any area of the stone and didn't rely on a naturally occurring fissure.


At Ollantaytambo transporting the large blocks required them to be lowered from the quarry area, hauled across the valley floor, over the Urubamba River, and up to the Temple site.
As mentioned above there are several large stones lying at the base of a large ramp which leads up to the Temple. They are called the "Tired Stones". As evidenced by digging under other stones left in the fields, getting them to this point was accomplished by dragging them over a prepared bed of cobblestones. Vincent Lee has suggested a method for getting them up the steep ramp, turning them and bringing them to the site.

Vincent Lee developed his method while working on similar problems on Easter Island. He devised a method that employs a track of ladder-like sections for the roadbed, a sled to place the stone on, and levers to move it forward. 

Dressing and setting the stones in the precise way that made Inca construction so famous is also not known from written history. None of the stonemasons' methods survived to present day. Many theories have been proposed. 
The most well accepted theory about how the Inca dressed the stones is that they used hammer stones to shape the blocks. Larger hammer stones were used to rough the blocks and smaller stones were used to finish and smooth the blocks. Trial experiments has proven that this is a viable method for reproducing the work of the Inca stonemasons. 




Setting the blocks presents an obvious problem. The stones are massive with many weighing several tons. Moving and fitting must be an efficient and simple process to be worthwhile. Many theories exist about how it was accomplished. Again Vincent Lee has proposed a reasonable solution that does not rely on space alien interventions.
Vincent Lee has proposed a process that is not far from the method used by log workers to build log cabins. Essentially a stone must be maneuvered into place above its intended placement. Then the stone may be scribed with the exact form of the placement below and lowered into place. Mr. Lee has developed  a method for holding the stones in place above their eventual location. His ideas seem to work well with the small protuberances and concavities seen at the base of so many stones. His suggested scribe tool has never been seen though and any minor refitting would be difficult to perform.

Cultural Context