The Seine is a 776 km (482 mi)-long river and an important commercial waterway within the Paris Basin in the north of France.

It rises at Source-Seine, 30 kilometres (19 mi) northwest of Dijon in northeastern France in the Langres plateau, flowing through Paris and into the English Channel at Le Havre (and Honfleur on the left bank).

There are 37 bridges within Paris and dozens more spanning the river outside the city.