Crop Circles, Fortresses, and Inca Warriors

Ollantaytambo Ruins

Manco Inca Yupanqui, king of the Inca people and general of the armies, looked down the steep terraces on Ollantaytambo at the oncoming Spanish army. “Fire!”, he said to his archers. But the Spanish kept coming. It was January 1537.

“Fire!”, again he called as the enemy came closer, this time to his spearmen and to anyone with a spare hand to throw a rock. The Spanish army reeled under the onslaught. Sensing an advantage he flagged his men in the hills; they let loose blocked canals and flooded the valley below.  The Spanish cavalry was swamped, and the Spanish general called a retreat. So ended one of the few major battles the Inca won over the Spanish.

Temple Hill at Ollantaytambo

Thanks to this one event the terraces and buildings at Ollantaytambo in the Sacred Valley of Peru became known as a fortress, but for most of its existence its use was religious or for astronomy.  It’s possible the battle didn’t even reach here, it was the last line of defense.

The lower and mid levels of the terraces at Temple hill are made of field stone. They’re arranged with skill, much as you might stack a cord of wood, but they do not have the dressed stone aspect of the top tiers. Our guide tells us that the terraces are likely pre-Inca, and the dressed stonework at the top came later after the Inca conquered the valley and opted to turn it into a regional administration and religious center.

Sacred Valley

Sacred Valley

Sacred Valley

This doesn’t mean the Inca only did fancy dressed stonework. That level of masonry was reserved for temples. But the bigger question is, how the heck did they do it?

Inca Dressed Stonework

No mortar was used. Individual blocks weighed from hundreds to thousands of pounds. Yet the pieces interlocked as tightly as a 3D jigsaw puzzle, without enough space between the stones big enough to fit a piece of paper. You’d think the Spanish would have asked.

Maybe they did. Maybe they decided it was too time and labor intensive to bother with. Maybe the Inca stonemasons were secretive, and would only share their techniques with apprentices who’d been sworn in, wearing funny hats and robes, and taught the secret handshake. In any case, the Spanish did not record the how.

Massive Doorway

One thing is clear, the Inca never finished their remodel. Some of the stones show clear signs of unfinished carving, and semi-completed stone blocks lay here and there.

Unfinished Design on the Wall of Six Monoliths

Atop the temple is a window that, only on the solstice, June 21, lets light through to strike a pillar. This signaled a change in the growing season.

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When you hear about Peruvian history, it’s always Inca this and Inca that. But the Inca empire was short lived – it only lasted from 1438-1533, less than 100 years. Huge amounts of preconquest Peru history predates the Inca.  And to split hairs (skulls maybe?), the name Inca only applied to the rulers rather than the riff-raff, it’s the Spanish who started its use as a generic term. So what’s the big deal?

The Inca people showed up around the early 13th century, and were just another tribe in the Cusco area until the reign of their 9th king,  Pachacuti (1438–1471). Pachacuti Inca Yupanqui made his name initially as a military commander, he defended Cusco from the Chanka while his father and brother turned tail and ran. Perhaps he took his victory as an omen, as he followed up by beginning an unprecedented expansion of empire, which was continued by his son and grandson. At its largest, the empire joined Peru, large parts of modern Ecuador, western and south central Bolivia, northwest Argentina, north and central Chile and a small part of southern Colombia into a state comparable to the historical empires of Eurasia.

Pachacuti and Sons didn’t do all of this at the point of a spear, they also used more diplomatic methods. That’s where the crop circles come in.

Crop Circles

When I first saw pictures of the “agricultural” terraces at Moray, I was thinking the archeologists had been sniffing too much dust, it looked like an amphitheater to me. But once I was on site and saw the scale of these terraced depressions it was clear that any actor would need to have the voice of a god to project from bottom to top. You’d need a big theater troupe as well, there were three of these “amphitheaters” on site.

Then the guide started talking about how the archeologists had tested the soil, and found that some of it was imported from other parts of the empire, and seeds of various sorts had been found at the different levels. It began to look like this really was an agricultural research station.

Not convinced? Consider this. Each of the terraces was engineered. It wasn’t just dirt, it was a layer of rocks, then a layer of gravel, then a layer of sand, then a layer of dirt. Peru’s climate is rainy season and dry season, and this helped prevent flooding in the rainy season. To top that off, there were irrigation channels that could be opened and closed to control how much water got to a section of each terrace.

 

Still not convinced? How about this: each terrace is about 5 or 6 feet higher than the next. When you add irrigation, that amounts to as much as a 3°F difference from level to level, and as much as 27°F (15°C) difference from the bottom to the top of a pit. So, they can not only test different plants, they can test them for different climatic conditions. Using this information, the Inca became so successful at farming they could not only survive, but build up food stores.

Peruvian Farmers Are Still Using Ox, Yoke, and Hand Plow…

So what does all this have to do with Pachacuti and Sons?

While Pachacuti had a reputation for being brutal, he wasn’t dumb. He knew he’d have better luck with his conquests if he could do so without violence, so he’d use a rough diplomacy when he could – both the carrot and the stick.  He’d send spies to the lands he was interested in and learn of their military strength, wealth, and food status.

Then he’d send ambassadors with gifts. They’d ask “how’s your corn crop doing”, knowing that the crops were suffering from lack of water. They’d say, “we have extra food we can help you out with now, and we’ve developed seeds that will grow in dry conditions. Would you like some?” They’d say “yes, thank you”, and the next year the ambassador would say, “if you want more help, if you want to be as prosperous as we are, you’ll have to join our federation.” Because that’s what the empire was, just loosely aligned tribes, paying taxes to the central Inca government and following their lead. Most would say “yes, we’ll join”, knowing full well if they didn’t the stick would be next.

But eventually the Spanish showed up, with their superior technology, and their diseases (smallpox in particular), and their aptitude for recruiting natives that had been subjugated by the Inca. Two of Pachacuti’s great grandsons had just finished a civil war over who was going to be the next king, and the Spanish used the residual animosity from that to recruit more natives for their army.

By the time the battle of Ollantaytambo occurred the Spanish were already in control. Manco Inca Yupanqui was actually a puppet king, the Spanish had put him in power. If they had treated him well he’d have probably worked for them, but they did not. He escaped and raised an army of 200,000 for a rebellion.  Ollantaytambo was a victory, but Manco didn’t think he could hold it in the face of Spanish reinforcements so he retreated to the jungle village of Vilcabamba. That remnant of Inca resistance survived until 1572.

When I started my day in the Sacred Valley I knew none of this. I had no idea how the Inca empire had grown so fast and fallen so fast. The idea of the Inca having an agricultural research station seemed ridiculous – weren’t they primitives? Judging by their engineering, maybe not so much. Judging by their brutality, maybe so. But have things changed that much?