Heidelberg or Trier...and why
 

Two days left on my itinerary and would like to spend two days in one of the other. any suggestions/comments would be welcome. Logistics not a problem; proximity to elsewhere not a problem; both of interest. Just looking for your expert thoughts/opinions...and thank you.

I'd go for Trier.

Heidelberg is nice, but it's a bit of a tourist trap.

If I remember, there wasn't too much to Trier besides the Roman Portal. I think that the trip to Heidelberg is a little more scenic and the castle worth it.

Don't get me wrong...Trier isn't bad; I just thought that Heidelberg is a little better.

Its a toss-up
 

Since you make an either-or proposition, I think Heidelberg edges by a hair. To do Heidelberg, 1 day should be sufficient, spend the second day to tour the Neckar river valley (assume you have wheels).
The Heidelberg Castle is what draws tourist here. But I found that the old town area with its Marktplatz is quite interesting, dotted with colorful buildings, winstubs and restaurants. It has several museums (being a university town with Germany's first U established here) in town. There is a good walk through the university campus and then across the Alte Brucke (Old bridge) to the castle. As previous post mentioned Heidelberg being touristic, that it is. But at night, the town is very nice and quite with all the tourists gone.

As for Trier, it is known for its Roman relics. If you are a student of Roman architecture and arts, Trier can be a great 1-day destination. Spare the next day driving along the Mosel river all the way to Koblenz (RT takes 1 day). I think the Mosel valley is worth touring. Again, it is best done with a car. Barring driving, trains and boats are open options.

Whatever you decide, have a great trip!

I agree with the others, both cities give you enough for one day. Heidelberg appears to be a "must" for US tourists whereas Trier is a "must" for Chinese tourists (not because of the Romans but because Karl Marx was born in Trier).

You can easily do Trier and Luxemburg (44 minutes by train) and you can do Heidelberg and spend a day in the vinyards at the banks of the Rhine.

One remark regarding German universities: Heidelberg is not the "oldest German university" but the "oldest German university on todays territory of the Federal Republic of Germany" and was founded in 1386. The oldest German university was - believe it or not - in Praque (1348), followed by Vienna (1365). All three cities were part of the German Empire of those days (by the way: ruled by an Emperor belonging to the Luxembourg family during those days - some kind of EU in the 14th century).

I study in Heidleberg, and yes it is a beautiful town, but that's about it. Tons of tourists and a lot of tourist traps (bad and expensive restaurants in the old town), I wouldn't want to go here as a tourist, although there are some nice spots and good restaurants, but not in the old town. I'd also prefer Trier and the Mosel region.
When you are already in the south, have you considered Lake Constance?

Trier:

-Birthplace of Karl Marx
-Scenic Mosel Valley nearby
-Luxembourg nearby

Heidelberg is nice too, take a coin :D

....or visit Wuerzburg instead ....

Wow, thank you all for the great insights and opinions...exactly what I was hoping for. Keep it coming..it's all very helpful.

I live an equal distance from both cities. I have been to Trier thrice and Heidelberg twice.

IMHO, I think Trier is a better tourist destination. The Roman ruins (Ampitheater/Porta Nigra/baths) along with Karl Marx' house are a bit more eclectic than Heidelberg. Heidelberg's castle and Marketplace are nice but pretty much the norm for Germany. If you have not seen the castles and such - Heidelberg may be better.
On the other hand - if you have enough time - Chateau Vianden in Luxembourg (near Trier) is as nice as any castle I have seen in Germany.

I have debated this same question with many visitors who have come to see us in Germany!

Würzburg is nice too, sure it is, it's my birthplace...:)

But as I said, keep the Lake Constance region in mind.

I don't know DTS from Adam (or Eve as the case may be), but the fact that he was born in Wuertzburg seems to me a better reason to visit that city than Marx's birthplace makes me want to visit Trier again. I've also heard that Wuertzburg is very interesting in any case.

My personal opinion is that you can't go wrong with either option. I find the Moseltal more interesting than Trier itself. If you choose Heidelberg the Neckertal is great too. Whoever mentioned that there are some great restaurants near Heidelberg was spot on. I don't know how you locate a good one, but the best Spargel I've ever eaten was in greater Heidelberg.

"Schwarz" right next to the main station has a Michelin star, it is situated in the top floor of a high building named "Print Media Academy", it gives a nice view over Heidelberg, definitely the best (but also most expensive) ending of a day in the Neckartal.

Trier, it fits better then Heidleberg on a postcard. And it is easier to spell. :) :p ;) :D

Trier is sometimes described as the oldest German city.

The Porta Nigra and other Roman sites like baths are quite interesting.

Heidelberg is "more American", so depending on your desires, Trier might be more "unusual".

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