Europe in September

You’re asking about three entire countries? Where specifically? Probably the general answer is that touristy areas will be touristed.

September is one of the most desirable times to visit Western Europe and in Paris for example, hotels are at their very highest prices then. So yes this is not an 'off season' time for either crowds or costs. It is also a very pleasant time of year especially since AC is fairly rare in these countries except in high end hotels.

Thank you, Janet.

I just returned from France from a 3 week trip with my husband. We mainly visited smaller towns but did spend time in Paris at the end of the trip and spent some time in Marseille and visited Lyon along the route.
I cannot say how much more busy it was than in the summer but I was pleasantly surprised that the bigger cities were not as crowded as I had was expecting. We visited the Louvre in Paris, but did it on a Monday morning , and it was not overly crazy except around the more famous exhibits. (Mona Lisa, for one.)
The smaller towns were lovely and not crowded at all.
I expect that summer would bring a lot more travellers.
The only site that was totally crazy was Mont St. Michel. I have heard that if you go after the tour buses have gone it is lovely. After we arrived it was wall to wall people and not fun.
I guess it all boils down to where you want to go and the timing of the visit.

August is the month of Holidays in Europe so not only do you have non-european tourists, you have european tourists, too. Typically the kiddos in France have la rentrée the beginning of September. If you chose to go late September, you will have good weather and fewer tourists.

The difference between the beginning of September and the end of September can be enormous: we were in Paris from September 5-14 with record-breaking heat--95-96 degrees F. We returned on September 17-19 and it was 25 degrees cooler! Take a look at timeanddate.com for accurate temperatures, precipitation, etc. going back at least 20 years to get an idea of weather.

Definition of "crowds" depends on where in France you are (I can't answer for the other two countries). We were in Paris last mid-late December during the infamous grisaille, so the museums were the most packed that I've ever seen them. It was unpleasant. The ground floor of 'Orsay looked like one of the biannual sales days at Harrods. This September, we did not enter one museum (that was refreshing!), so I don't know about crowds in them. The streets were nicely walkable (but, then, I compare them to Manhattan which is a nightmare, especially in the summer). I'd do it all over again in a heartbeat, though. . .

Thank you for your responses. I'm a little confused about September, however. (In France) One person says it's not as crowded, and another says it's very crowded. I suppose it depends it you're going to small villages or major attractions. We may go down to Florence, which will probably be a zoo either time.

A general, Europe-wide comment about crowds may not be very applicable to your specific plans. And "less crowded" may still be really bad. It comes down to which cities you plan to go to, which attractions you want to visit, and how uncomfortable you are with crowded transportation and sidewalks in the vicinity of the top sights. You'll find crowds on the sidewalks in a city like Rome any time of the year. They may be mostly locals, but it's still crowded.

I've read many times on the forum that Paris hotel rates peak in September. A good bit of business travel is involved--that's the month of Fashion Week and no doubt other events--so perhaps a good number of those folks are not going to the Louvre. I'm sure sights are very busy in any case. As for Italy, you can check the (lack of) availability of entry tickets for the Vatican Museums and observe how very busy Rome is now. The first date with online, regular-entry tickets available is November 6. Anyone needing an earlier ticket must go stand in the usually long and slow outdoor ticket line, choose a more expensive package deal from the Vatican (with lunch, etc.), buy a more costly commercial tour, or try to pick up a ticket at an inflated cost from a third party that has extras.

https://tickets.museivaticani.va/home/fromtag/1/1696107600000/Biglietti-Musei

It's a simple fact that the times of the year with the most pleasant weather are popular. There are plenty of folks who aren't limited by school schedules and can travel in April, May, September, and October if they want to. If you haven't been to the super-busy cities during the peak summer months, conditions in late Septemver and October will still seem unbelievably crowded. The way to avoid crowds is to avoid the most popular cities, but few travelers are willing to do that.