A team of Iranian archaeologists has recently discovered 20 meters of a canal of the sewage system buried 5 meters underground in Persepolis (now southern Iran). Source: Tehran Times http://www.tehrantimes.com/arts-and-culture/98454-part-of-persepolis-sewage-system-unearthed
It does, doesn't it? I never managed to figure it out how do we manage to disregard previous knowledge so easily.
