Some of the world's oldest cities had better sanitation than Victorian London.

A household bath had somewhere for its water to go

At Mohenjo-daro, a bathing area was not simply a corner where water collected on the floor. Many homes had a built bathing platform, often made of tightly fitted bricks, with a slight slope toward an outlet. Used water flowed from the house into a street drain rather than spreading through the rooms or pooling outside the doorway.

That small connection mattered because the drains were part of a larger, coordinated system. Covered channels ran along streets, carrying wastewater away from homes. Their brick construction and access points made it possible to inspect and clear blockages—a practical necessity when drains carry household waste day after day.

Sanitation depended on city planning

A sewer works only if the buildings, streets, and drainage routes fit together. Mohenjo-daro’s system linked individual homes to shared infrastructure, so sanitation was not just a private feature for a wealthy household. It required builders to reserve space for drains and maintain routes through densely settled blocks.

The evidence does not mean every resident had a modern toilet or that the system eliminated disease. These were drains for wastewater, and ancient sanitation had limits. But the arrangement shows a strikingly early understanding: removing used water reliably takes planning beyond the walls of a single home.

London’s problem was a different scale

Victorian London faced a rapidly growing metropolis whose waste overwhelmed older arrangements, including cesspits and drains that discharged into the Thames. Sewage in the river became part of a public-health and infrastructure crisis, prompting major sewer construction in the nineteenth century. The contrast is not that ancient cities had solved sanitation for all time; it is that Mohenjo-daro had built household drainage into its urban layout thousands of years before London could manage its own waste at metropolitan scale.

In Mohenjo-daro, the route from a bath to a covered street drain was part of the house from the start—a reminder that sanitation begins with where a city decides water should go.