Banned for a century because of the filthy water, city swimming is set to be one of the major legacies of the Games thanks to a €1.4bn (£1.2bn; $1.6bn) regeneration project universally hailed as a success.

Not only are three Olympic events - triathlon, marathon swimming and paratriathlon - scheduled to take place in the Seine in central Paris, but by 2025 three open-air swimming areas will be accessible from the quayside.