But because Valencia has regularly seen terrible floods, including floods with many deaths, with water reaching as high the second floor of some houses (!), at some point it's been decided to divert the Turia so that it doesn't flow in the middle of the city anymore.
Many cities have been build along a river and then spread on both side of the river: be it Paris, Prague, Brussels, Budapest (literally the name of the two sides of the river: Buda and Pest), etc.
But Valencia is magical in that the river has been diverted and most of the old path of the river has been transformed into garden / bike paths / run track / etc.
It's like if you were to take Paris, divert the "Seine" and in its place put a gigantic garden.
IMO more cities should do just that: Valencia is the proof it can be done.