Ladies and gentlemen, the mighty Seine River! Stretching its watery arms between Paris, Rouen, and Le Havre, it travels almost 200 km before diving into the English Channel. Despite centuries of human interference, our resilient Seine has flowed similarly since 12,000 BC.

As a centennial river, the Seine has a one-in-100 chance of flooding each year—like in 1910, when waters hit a record 8.62 metres above the Pont d’Austerlitz, forcing Parisians to travel by boat. Over the centuries, the Seine hasn't just influenced commerce and culture in Paris; it's also shaped how Parisian streets are numbered. Streets crossing or angled to the Seine start their numbering from the side nearest to the river, while numbers on parallel streets increase with the river’s flow.