In 2014, archaeologists working along Hadrian's Wall in Northern England found something amazing.

There, at the bottom of a mud-filled pit of garbage, was a perfectly intact 2,000-year-old toilet seat.

Historians had already learned a lot about Roman toilets over the years, but this was the first time an actual seat had been discovered.

It was carefully carved from a single piece of wood, and had a shape that would be instantly recognizable to any of us today.

That narrow, sea-shaped curve that sits between the toilet itself and the person using it.

It's become part of the universal language of sanitation, along with pipes and running water, all of which are tools designed to keep us clean.

The rise of major civilizations has always tended to run parallel to their access to fresh water.

The Romans are a prime example of this, their massive network of 11 aqueducts, which delivered roughly 300 million gallons of water to them each day,

allowed them to grow and flourish as a culture.

Without fresh water, we might not have had the Romans at all.

History is littered with our mistakes, though. Poor conditions led to an outbreak of typhoid fever in Athens around 430 BCE, killing a quarter of the city's population.

The plague of Justinian raged across the Byzantine Empire for almost two centuries, and by the time it was finished in 750 AD, half of Europe was dead.

600 years later, the plague returned to claim millions more.

Over the centuries, humans have proven the old adage that cleanliness is next to godliness, that being clean is the best way to stay healthy and fight disease.

When we do it right, a society can be transformed, elevating the quality of living to a whole new level.

When we fail though, bad things can happen.

And sometimes, as history has shown us, those bad things have been intentional.

I'm Aaron Manke, and this is lore.

The city of Fiodosia, once called Kafa, is an ancient seaport on the eastern side of Crimea, the peninsula that juts down from the north into the middle of the Black Sea.

It was founded nearly 800 years ago by Italian merchants from Genoa, who were given permission to settle there by the Mongol Empire, the biggest kingdom the world had seen up until that moment.

By the early 1300s though, relations had soured between them.

Mongol rulers felt that the Genoans were a bit deceitful and disloyal, and after years of tension, they sent forces to reclaim Kafa for themselves.

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