Last Minute trip feasibility

Of course it's feasable. I just started planning a trip that starts in the middle of October and runs through the end of the year. When I say started, I mean I'm still figuring out where I want to go in Europe.

Instead of renting a car from Berlin to Munich why not stick to trains. The German rail network is extensive you can easily find places to stop between those two cities. (If you like history, consider Nuremberg.)

And from the train, you can look out the window and enjoy the scenery. Not easily done when you're driving a car.

The train from Munich to Brussels is at minimum 6.5 hours long with multiple connections. I was going to suggest going from Frankfurt and then Berlin but the trains from Berlin to Brussels are about the same as the ones from Munich.

Totally feasible. What is your interest in Brussels? It's not all that close to your other cities. There are lots of fantastic places around Berlin, Munich and Paris. Off the top of my head, Dresden, Salzburg, Strasbourg, Tours, Rouen, Giverny, Reims, and I've not been to Frankfurt, but I've heard its a great city to visit, and there are interesting cities close to Frankfurt (Koblenz, Bingen, other Rhine cities). Your selected cities are all quite big.You might enjoy having some smaller cities in the mix.

SInce its your first trip, I would do all trains.

I agree with jules m-I don't see how Brussels fits your interest in culture, history and natural beauty. I would spend that time in Germany or France. I have been to Brussels because it was on the way to Ypres, but found it to be a complete waste of time. I loved Fussen. The small museum there is interesting.

Badbie,
Congratulations on your first trip to Europe! Don't worry about last minute. I agree with Jules and cala about Brussels. Compared to Bruges and Ghent it is a disappointment.

If I am guessing correctly, you will leave the states on the 8th and fly back on the 28th. Is that correct? If so, you will have 19 nights there. (Arriving on the 9th). You might want to spend that first night in Frankfurt to adjust to the time difference and get over any jet lag. Or with good train connections, then, yes, go straight to Berlin. Stay 3-4 nights. (That is just 2-3 full days.) The drive to Munich from Berlin takes 7-8 hours and takes you through Nuremburg, where I would definitely stay 2 nights. Munich deserves at least 4 nights (3 full days), IMO. Turn in your rental in Munich. This uses up 10-11 nights. I would skip Belgium this trip, but if you go, fly and spend your time in Bruges, not Brussels. Remember you have lost a day to travel between Berlin and Munich. Of course, you will experience Germany as you drive. You will use a day after Munich either going to Belgium or to Paris. Personally, I would use all the days left In Paris.I consider it to be the capital of Europe and an unforgettable experience!

So, to recap (just my suggestion of course).....
Nights 10/9-10/12 Berlin (3 full days)
Nights 10/13-10/14 Nuremburg (remember most of 10/13 will be driving from Berlin to Nuremburg, so 1 1/2 days)
Nights 10/15-10/18 Munich (you will arrive before noon, so 10/15 will be almost a whole day there, so 3 3/4 days)
You can turn in the car on arriving in Munich unless you have plans for some side/day trip from there. Otherwise turn it in when you leave Munich.
Nights 10/19-10/22 Belgium (fly from Munich to Belgium on 10/19, so 2 full days there...travel on the 19th will take up a good chunk of the day) Train to Paris on the 23rd, about 3 hours.
Nights 10/23-10/27 Paris (4 full days, plus part of 10/23 after a 3+ hour train from Belgium)
Day of 10/28 fly home.

IMO, Paris deserves the most time, so this trip I would skip Belgium and fly to Paris from Munich. But that's me.
Please remember, this is YOUR trip. I just highly recommend figuring out the method and time involved moving from city to city, and counting nights, which lets you know how much you can do and see. With that advice, I defer to your wishes.

Bonne chance and bon voyage!

I suggest you get a copy of Europe thru the Back Door for your first adventure. It is full of great advice. Advice such as getting a business card from you hotel, take it from experience as we got lost in Strasburg and couldn't remember our hotel. This was before cell phones. I totally obscenely over packed now can go for three weeks with an overnight bag. Also remember we all had our first trip and mishaps and lived to return to Europe. Also ask for help on this site using the country specific sections for advice on hotels, sightseeing, restaurants. etc. So exciting for you. Just the magic of it all!!! Good luck.

October is a nice travel month. I want to follow up on Frank II's idea and suggest a train-only strategy...

You can reduce your stress a lot by not rushing your planning too quickly. October is not an intense month for travel. And if you take the advice to use trains only in Germany, you won't need to make any car reservations or any train reservations or pin down specific train times if you go with a German Rail Pass, which allows for X number of travel days within 30 days (flexi-pass and twin-pass version.) You do not have to buy this in advance. It is available in Germany. It's perfect for last-minute planning.

https://assets.static-bahn.de/dam/jcr:87153f1d-08e1-481e-8aae-b5fffe7090b5/German_Rail_Pass_brochure_2025.pdf

https://int.bahn.de/en/offers/german-rail-pass

Price table:
https://assets.static-bahn.de/dam/jcr:6ef53210-8ff6-46eb-ae82-34d2fd953891/GermanRailPass2025_IntBahnDe.pdf

(Note: The German Rail Pass DOES provide for the use of CERTAIN trains between any German town and BRUSSELS should you decide to go there. See the first link I provided above for details.)

With your core ticketing decided, you can now focus on your itinerary. 3 weeks... let's say you stay in 6 different places. Berlin/Munich/Füssen + 3 more... (Using some places already suggested...) Maybe Nuremberg just before Munich? Maybe Koblenz (#5) after Munich and after that, a Rick Steves suggestion, Trier. (#6.)

6 destinations = a 5-day flexi-twin pass €478/2 persons.

Then as you read and plan in the coming weeks, you can make any substitutions you like without any ticket changes. Maybe you decide Stuttgart is better than Koblenz for example. Done. You don't have to decide the travel dates in advance either.

Use the DB schedule to find train travel times - but if you want to change your plans as you go, again, there is nothing you must change. Your plan says you leave Munich at 8 but you want to postpone your departure time. No sweat, just show up for the 9 or 10 o'clock train instead.

DB site: https://int.bahn.de/en/

TRIER: I like this destination for many reasons but in part because it's near the French border and makes it simple to reach Paris. 9:33 - 12:52 with 1 change in Saarbrücken. That's faster than from Frankfurt, btw. It is a good idea to pin down your FINAL destination in Germany as you will need to buy your one-way train tickets to Paris ASAP.

Punt Brussels, add days to Paris.

You all are SO HELPFUL!! Thank you. We will definitely not do Brussels (maybe Ghent ?).

I can see why you would choose to see Brussels since you have history listed as one of your interests, and that depends on your level of interest in history. If you're interest also lies within the realm of war history, then I suggest seeing Royal Belgian Military History Museum. Plus, south Brussels is Waterloo.

That battlefield site takes up an entire afternoon....all depends on your level of interest, I saw it once in 1984, spent close to 6 hours exploring all aspects of the battlefield plus some of the town which housed more information on the battle, still it wasn't enough time.

If neither war history nor Napoleon's utter defeat is the driving historical reason to see Brussels, then I would suggest skipping Brussels. On WW1 in Belgium there's Mons

Instead of renting a car from Berlin to Munich why not stick to
trains. The German rail network is extensive you can easily find
places to stop between those two cities.

Some specific suggestions in addition to Nuremberg:

Erfurt - a charming,compact, and walkable town. UNESCO World Heritage site. Roughly half way on the main ICE railway between Berlin and Munich: https://www.erfurt-tourismus.de/en/all-about-erfurt/places-of-interest/

Bamberg - Also UNESCO WH. Roughly 50 minutes beyond Erfurt as you travel toward Munich. Well-preserved medieval town center, cultural icon for Franconia: https://whc.unesco.org/en/list/624/

BOTH rail stations for these cities have lockers for bags if you wish to sightsee for a few hours.

Alternatively, book 1-2 nights in one, the other, or both for a more complete visit.

Skip Brussels, unless you want to see Brugges.

To me, taking the train to Berlin and then driving to Munich doesn't make any sense, geographically. October isn't as last-minute as you think it is. Make a list of places you want to visit in Germany, the Netherlands (Amsterdam!), Belgium and France (because these countries are all very accessible from Frankfurt). Figure out how much time you need in each place. Explore the connections between these places, and see what makes sense to keep and what to save for the next time.
If it were me, I would pick up a car at FRA and stay the first night in a nearby spa town (last year, it was Wiesbaden, which is not a town but a city, but it's very close and was a great starting point for a couple of days in Mosel Valley, which I highly recommend). The thermal pools are a great way to recover from that long flight. "Nearby" being a relative term. I don't think I would go as far as Baden Baden, which is probably a 90-minute drive.
Anyway, make your way to Munich (this could easily take a week if you stop in Bamberg, Nuremburg, etc.), turn in the car, and from there, take a train to your next destination. Here is the info on train links from Munich:
https://www.seat61.com/international-trains/trains-from-Munich.htm

I'll pile onto the side of take trains everywhere.

That said: deferred maintenance on Deutsche Bahn means that their timetables can be... suggestions more than sacrosanct. If you have some time flexibility they are great, but if you have hard travel start and stop times (e.g. you book a flight from MUC to CDG) then you'll want to plan some flexibility.

If you want to take trains from Munich to Paris, then catch a SBB (Swiss Rail) train from the Hauptbahnhof. The Swiss train will run on time. The route it takes is also super scenic, via Zürich, Bern, and then to Geneva along Lac Leman (yes, you'll need to change trains along the way - not a big deal if you travel light). Once in Geneva, switch to SNCF to go to Paris. Note that this is a long journey, and if you want to spend an extra day in Paris you may be better off taking a short-hop flight between MUC and CDG (basically a flight every hour from Lufthansa or Air France).

Driving in Germany isn't terrible, but it's also not without its own challenges. Parking can be tough in some cities and towns, some roads will seem narrow, and you'll want to familiarize yourself with international traffic signs (the U.S. is an outlier in terms of signs compared to basically everywhere else in the world). And you don't really enjoy the view as much when driving because you have to pay attention to traffic, speed zones, etc.

In other words: trains and public transit (buses, trams, etc.) are lower stress and often have great views.

You'll have 19 practical days on European soil - enjoy them! Don't feel rushed, soak it in. Breathe. Have fun!

Just a thought: figure out your trip without renting a car, maybe? The post above mine makes some good points about the stress of driving, and it occurs to me that I did not rent a car in Europe for the first time until I had made quite a few trips over there (on my first trip back in the day, I connected all the dots with a Eurail pass).

Do yourself a favor and save the joy of car rentals for another trip...take trains or planes this time.

Have you thought about spending that 1st night in Frankfurt and then taking the train to Paris in the morning? Only 4 hours. From there you can start moving in a circle to Belgium, then to Berlin, etc. Fly home from Munich?

Or go the opposite direction. Look at a map and see how the cities best link up. Trains are your best bet.