This is Moray Peru and it is a massive project that was started before the Incas and the upper layers are still in use today.
The Incas and the culture that built these "structures" were using the different layers to test what king of foods grow best at what latitudes. It was an ancient study of botany and from what people can tell the ancient Peruvians were damn good at it. Maybe better than modern people are.
Not much to do back then if you were a farmer other than watch chit grow.
Anyways, go ahead and read up on the amazing culture and their achievements.
I took these photos and have all rights to them.