The Cloaca Maxima
Photograph: Roger Wood/Corbis
The large sewage system that the Romans built through the heart of their capital, was the first of its kind, and in an odd tribute to that extraordinary people, is still functioning today (as is its equivalent in York). The Romans built collective toilets, similar to the one above.
Far too many Indonesians do not have proper toilets and use fields and rivers for defecation.
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