In France, that would still be Lyon because the economy's always been pretty steady over there.
I would hold it as a pretty aggressive town in business, by tradition.
Although Bordeaux, whose genuine 18th-century historic downtown feels very good and attractive might turn a serious challenger since it's been connected to Paris by a HSR line.
It takes only 2 hours for the 600km ride by train now, like you can almost travel the round trip on a daily basis, given today's work amenities.
As a result, it's been madly gentrifying at faster rate, which of course is causing some issues to the local working and middle class people.
Toulouse is also doing good as the major hub of the aeronautical industry in Europe.
It is actually the fastest growing city in the country, but it's rather suburban. To my knowledge, the way I see it, people like their single-family homes with pools in backyards over there, so it's no real urban reference. That may cause some issues to them too in the end, and I hope they work more seriously on their city density.
Population-wise, Marseille should obviously be a candidate, but their downtown is such an impoverished mess that it's still hard to take it seriously.
It's like an American town in the 1970s/80s. The bourgeoisie lives outside the city proper over there, much like in Toulouse.
Nice is nice and kinda sexy as the largest city on the Riviera, but the local economy's yet too slow to make a nominee of it.
And Lille where I've never been yet is the northernmost larger city of the country, almost Belgian, which doesn't necessarily helps.
No kidding, it seems to be a pretty cool town however, but I don't see it as a rival of Lyon yet.
So it'd be either Lyon, definitely the most legitimate to date, or Toulouse or Bordeaux as rising challengers.