So where does that image of a dirty, unhealthy city come from? “Especially from the 19th century”, says De Kam. “That was a century full of infectious diseases such as smallpox and cholera. The city became fuller and dirtier and diseases could spread more easily. At one point many people realized that they could not live on like this. Government, the medical world and citizens together made a They mainly looked at a cleaner city with water pipes and sewerage, but also at dealing with each other differently. Just like now with Covid: don’t cough in each other’s faces, don’t spit on the street and wash a lot.”