Moray (Inca Ruins)
Nearby to the previously posted Machu Picchu, Peru, is a very unusual archaeological site – the strangely beautiful Inca ruins of Moray.
The concentric rings clearly visible were farming terraces with a sophisticated irrigation system, constructed inside enormous natural depressions in the landscape. Supposedly the Incas built them here to experiment with the different farming conditions the landscape accommodates, as the annual temperature difference between the top and bottom can be up to 15°C (27°F).
Which is fairly impressive given that even this largest depression is only 30 metres (100 feet) deep.
Here’s the very brief Wikipedia page.
Thanks to Josh E.
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uf, it looks like E.T.
uh, yes, 15ºC = 59ºF but a 15ºC delta = 27ºF delta
Still, very cool.
KarlC, thanks for the correction (not that I really understand it…!), however, surely “cool” would depend on where you were standing, right?
Alex, KarlC’s got a good point: the difference between 0C and 15C is 15 degrees C.
0C = 32F, 15C = 59F. So the difference (or delta) in Fahrenheit is 27F (59-32)…
Russ, I now feel very stupid
Thanks for explaining that, post updated!
I see the hand of some evil genius here: building giant circles for his doomsday device, blaming it on the Inca´s and then stealing 32 degrees Fahrenheit…