Side trip to Luxembourg?

It depends where your trip takes you! For example, if in Germany you visit Trier or the Mosel valley, then yes, why not. But if you're not coming within 2-3 hours of Luxembourg, the side trip for just one night is not worth it my opinion.

Any question that contains the phrase, "is it worth it?" is impossible for others to answer.

"Is it worth it?" ultimately boils down to a personal choice, because everyone has their own tastes and preferences. But it's more slippery than just that. All travel choices (like many of life's decisions) boils down to trade-offs.

We all have limited time (and limited money, though I think for most, time is our most constrained commodity).

The real question is, if you choose to do something, then what are you willing to forego in order to do it?

Is there anything worth seeing in Luxembourg? Absolutely. But a more useful questions would be, if I spend a day in Luxembourg, is it worth trading away a day that I would have otherwise spent doing (insert a list of all your other potential ways to spend that day here).

I'm actually a fan of Luxembourg (it also has a sentimental place in my heart because it was the first place I landed in Europe on my first trip). Luxembourg is under-appreciated by North Americans (though it does get its share of European tourists from nearby -- it won't be "empty"). There are cute towns, castles, beautiful river valleys and natural places, a rich history, a cute and dramatically-situated capital city, and relatively few crowds. If you have plenty of "days" on your trip, it's absolutely worth a day or two. But most folks have very short trips to Europe, and itineraries that try to pack in lots (often too many) more famous bucket-list places.

If you have time to spare (lucky you), yep, there's worthwhile stuff to see, and it's close to lots of other more touristed places you may be going to anyway. But it depends on your overall plan, including your itinerary and pace...and your tastes.

Luxembourg was a great place to unwind after my transatlantic flight. About 11 years I relaxed there for a couple of days before beginning intensive 4 week travel around Europe.

Is it worth it depends if you're considering the trip logistically. If you were closer, say within 2 hours, then I would advise it.

I know I should done a side trip to Lux. in 2001 when I spent five days in Metz, could have been easily done Metz to Diekirch as day trip. likewise to Thionville, which was last minute, making it more pricey.

Which places in NW Germany? I've been to numerous places big and small in that area. Nice towns to visit both from a cultural and historical view.

I have always enjoyed Luxembourg...and it is often overlooked simply because it's just beyond the places where we all tend to go.
If I were in Dinant (The Triple Moine is worth the trip) I would certainly consider a diversion to Luxembourg.
In this area you are also close to Reims France and the area between has immense WW2 historical significance. So for me, Reims (and a bit of bubbly, Dinant with a run through the Ardennes, Luxembourg and then North. We have rented a car in Paris to make this trip. We visited Northern Belgium and then the Netherlands. We dropped the car in Amsterdam.

@Fred - I'm in the VERY beginning of planning, so I'm open to suggestions for NW Germany!
@Mack - I'm a big fan of "open jaws" travel, but car rentals can be cost prohibitive (at least in the US). Was it much more expensive to leave the car in another city? Also, I didn't know it was possible to rent the car in one country and drop it off in another. That's helpful!

It's almost always possible to rent a car in one country and drop it off in another. However, doing that often comes with a very large surcharge. Not always, and not always very large, but often (usually), so you need to shop the rental agencies to see how bad the damages would be and compare prices carefully. Sometimes, especially if the drop-off fee is not terribly high, it may make sense to do it anyway, because it can simplify your routing and open up more creative routing options. There's no way to know without checking with the agencies (especially these days, it's critical to shop around anyway).

There have been times when I went to great lengths to "beat" the large drop-off fee (eg between Spain and Portugal), taking a combination of buses, a ferry and crossing the border on-foot (also Slovenia to Croatia). Other times (Lithuania, Latvia, Estonia) I just ate the dropoff fee, because it wasn't huge and enabled a more favorable routing. It always depends on the specifics, so you gotta get real numbers.

@ PghJennifer.....In NW Germany I would suggest these cities and towns well worth visiting, Münster and Soest, both of which are in Westphalia. Further east, not really in the north west are Minden an der Weser, Hildesheim, and Hameln....I especially like Minden, was there a few times, especially interesting and scenic is the Zentrum.

Other places I would suggest in NW Germany depending on your interests, if those interests include history.

Bottom line....NW Germany has some lovely scenery.

I don't recall that there was an additional charge for the drop in Amsterdam. Frankly, even if there was I would have absorbed it as part of the trip. We had very specific places we wanted to go, but we also wanted to have the flexibility to ram around aimlessly without being locked into public transportation schedules. We used public transportation in the Netherlands after we dropped off the car but in France, Belgium, Luxembourg we never could have gone to most of the wonderful places we explored if we did not have it. Whatever money we spent on the car we saved by staying only in AirBnB's...something I am not sure we would still do, but it worked out really great for us.