Aztec latrines were surprisingly fascinating:
They parked dugout canoes in a canal, and you would do your business in an outhouse directly above the canoe. After the canoe was full, it would be shipped down the canal to the low-lying pond-farms on the outskirts of Tenochticlan, set aflame to sterilize its load of waste, and then spread as fertilizer.
As a result, the city apparently very rarely had outbreaks of waterborne diseases, and crops seldom had to be rotated to restore phosphorus and nitrogen. Much better than the then-existing European method of "just pour everything out your window into the street."