Day trip from Paris... no castles

Have you considered Bayeux? I think it ticks all your boxes. The Bayeux Tapestry is definitely worth seeing, the cathedral is beautiful, and it has all the medieval charm you could hope for.

It's about 2 hours by train from Paris, so I don't know if that's too far for you to go for a day trip, but do a little Googling and see if you like what you find.

I liked Chartres and we purchased tickets day of for about 10euro. The cathedral of course is spectacular but I didn't know ahead that the town itself is quite charming. We walked along a small river for about a mile. It started behind the cathedral. If you are willing to stay late there is a light show on many of the buildings.

EDITED to add, we purchased train tickets day of. There is no admission charge for Chartres.

You can day trip from Paris to Giverny , Provins, La Roche - Guyon, Chantilly, and Marly-Le-Roi. All these wonderful small towns are a short commute from Paris. Provins is a medieval town. See Link below.

https://www.google.com/search?q=provins+france&rlz=1C1GCEU_enUS822US822&tbm=isch&source=iu&ictx=1&fir=hDmb2MI1hbFZZM%253A%252CilToPbghJcH-iM%252C%252Fm%252F03cz_1&usg=AI4_-kTNzW3rlarG09P2IN4pjjEp1oGKSw&sa=X&ved=2ahUKEwj004eh3LvgAhWnct8KHVKXBr4Q_B0wDHoECAEQBg#imgrc=hDmb2MI1hbFZZM:

I'd vote for Chartres as well. Gorgeous cathedral with interesting stained glass. If you are there at the right time you might be able to catch a tour with Chartres scholar Malcolm Miller. DO pay the extra small sum and visit the Crypt on a guided tour. It's in French only but they give you an explanation sheet in English. The crypt is not open except for the guided tours. You can just buy your ticket on the day at Montparnasse but if you are in the area the day before it may be quicker to get it then.

http://www.cathedrale-chartres.org/en/,143.html

The three cities you've mentionned : Rouen, Chartres and Reims are good options.

If you are interested in Joan of Arc, then you should go to Rouen where there is a nice musuem telling her story. If you go there between 6th and 16 june, there is the Armada de Rouen a big gathering of old boats. It's a very nice event and of course a very crowded one !

Chartres is the smallest of 3 cities, but it is located on a hill - something to take into consideration regarding walkabilty.

Finally, Reims is the closest by train (45 minutes if you take TGV high-speed train). The most famous attraction there is the Cathedral, that was recently renovated. Also if you are a Champagne lover, you could do some great tastings there.

V.

I haven't been to Chartres yet (which sounds lovely), but between Reims and Rouen I'd definitely choose Rouen for charm. Reims has a magnificent cathedral and some other sights, but the architecture is overall just not as attractive as you'll find in a lot of other French towns. A large chunk of Rouen's historic center was restored/rebuilt exceptionally well after it sustained major wartime damage.

An option with relatively few foreign tourists--though it's quite popular with the French themselves--is Troyes. It's 1-1/2 hours by rail from Paris Est on the TER, so no advance purchase is required. The historic center is full of higgledy-piggledy half-timbered buildings. And I saw nary a tour group in the 36 hours I spent there.

There are dozens of good day trips from Paris and you don't need to be going great distances. Given for your desire for medieval charm I'd recommend Senlis as the best bet
https://janettravels.wordpress.com/2010/06/12/moyen-age-visit-to-senlis/
There is no train station in Senlis but you buy a combo ticket of train to Chantilly and then bus ticket to get to Senlis. Easy trip and by far the best medieval village in the region.
Chartres has the great Cathedral, Rouen is not medieval but has interesting architecture (lots of half timber) quite different from Paris. Moret su Loing is charming
https://janettravels.wordpress.com/2013/03/03/moret-sur-loing-for-charm-always-follow-the-impressionists/
as is Crecy la Chapelle
https://janettravels.wordpress.com/2011/10/25/crecy-la-chapelle-a-touch-of-venice-in-the-parisian-countryside/
Provins has medieval walls and in summer they do falcon shows and archery and such for tourists.
Reims is a nice day trip but for the Champagne Houses not for medieval charm.

My favorite Paris day trip is Chartres. It's not much more than an hour by train. It's a very charming small walkable town with a great cathedral. My only regret was not staying into the evening for the light show.

Reims is reachable as a day trip. It also has one of the great cathedrals but I don't consider it as charming or walkable as Chartres. If a champagne house tour would be a top sight for you, Reims might be the place. There's a funky train connection to get from the fast train into town that adds some time both ways.

Rouen is about a two hour direct train ride. The medieval center is fairly huge and starts a few blocks from the train station. It ends up being a lot more walking than most places.

You can also get to Loire Valley fairly easily from Paris, but sights are spread out so I don't consider it a day trip.

Wow... lots of great suggestions. Thanks!

Bayeux looks interesting, the only thing is it's a little less than ideal in terms of distance from Paris. Based on your suggestions, I think I'm currently leaning more toward Chartres which looks like I can easily get to via TER. Rouen is still an option too, but it looks like that is on Intercités. Is Intercités another service that I can just purchase a ticket on the day of?

Yes you can purchase Intercité tickets the same day you travel (unless the train is sold-out, happens sometimes during weekends).

For Rouen, the train starts from Gare Saint Lazare, consider coming there in advance ( at least 20 to 30 minutes) so you have enough time to purchase tickets ( its faster from automatic machines than from the counter).

Chartres meets all of your requirements, one of the best day trips from Paris. Very quick and easy to get to, lovely and easily walkable and no need to buy tickets ahead of time.

If Chartres (which is great) does not ring your bell, Rouen makes a great day destination from Paris. Especially if you take in the Monets first at the Marmatton.

Like acraven already noticed I would go to Troyes, loads of charm, half timbered houses and several gothic churches like the cathedral. The whole historic city centre is well preserved and very walkable, there are several small museums like a stained glass and a pharmacy museum. Have to say I didn't visit them (edited) last September, however think they are worth a visit. About 1½ hour by train from Paris.

In case you go to Chartres, worth a visit is Château de Maintenon too on the same train line, you don’t need to buy an extra ticket if you travel the same day.

It's 2 hours each way by train, but Honfleur looks like it could work for you..

There’s no train station in Honfleur.

Sorry. I meant by bus.

Highly recommend Ina Caro's book Paris to the Past. It's an outstanding look at French history, but really focuses on the places like Chartres that can be reached by train from Paris. It really opened my eyes to the options that exist for those who stay in Paris and want to explore beautiful historical sights via the high-speed train system.

Wow... the amount of replies has been amazing!

Bruges is definitely on my radar but for a day trip, it's a little far for me. I've narrowed my choices down to Rouen and Chartres. Earlier, I was leaning toward Chartres but now I think I'm leaning more toward Rouen. As someone mentioned, the architecture is less medieval but still very interesting. I like the half-timbered houses. Rouen seems walkable and there are some museums there. Plus, it's in Normandy so I'd be in Camembert country... which is a plus for me.

By the looks of both, I feel like I can't go wrong either way, and they're both accessible by regional train so I'll just decide on the day. Thanks again everyone!

I will be there for several days, so I'm willing to sacrifice a bit of time and/or money for the flexibility of being able to decide which day I go. For example, if I book a ticket in advance and it happens to be pouring rain that day, I'd rather be visiting museums in Paris. And if Rouen becomes too expensive on the Intercités that day, I can just go to Chartres on the TER instead.

That's one thing I really liked about the Netherlands... you could go all over the place on the regional trains. Though I realize France is larger.

I just checked online tickets to Rouen for tomorrow morning to get a sense of how much they would be to buy at the last minute. I see they are about €20-24 per direction. Is that the typical price or are they more expensive at the actual station?