Having been to both cities, neither during high season, I believe they both have their charms and drawbacks. All have been mentioned in previous posts.

If I were you, I think I would opt for Venice on this trip, it seems more convenient, as you have arrangements already made.

Dubrovnik isn’t going anywhere; is it possible you will have a chance to explore it - and other parts of Croatia - in the future?

Many parts are underwater, its dirty, its thronged with tourists and overall seems gimicky.

Well some parts ARE underwater, like the canals, but other than that I did not find those other things to be true. I would use words more like fascinating and magical and unique.

"Gimicky" ??? It's a classic historic city. I really don't understand that one!!!

You have only two days. Not much time to do anything when you add in travel time. Venice would be my choice if you must choose one or the other--easier and faster to reach. I've been to Venice four times, the last time a year ago for a week and at the end of the week I wanted to stay longer. I never tire of Venice. The cruise ships have turned parts of the city into a circus. But most of the day trippers stay around St. Mark's Square. The best parts of Venice are away from that area (well, except for the basilica and the palace, of course). At night the city is magical.

Another option is to stay close to Rome. One hour away by train is the hill town of Orvieto. Take a day trip outside Rome to Villa d'Este. There are many places to visit a short distance from Rome proper. Save Venice and Dubrovnik for a time when you can do them justice.

Diane

Why numbers alone don't tell the story
 

Fair question!
1st time - to get out of hellacious July heat and tourist throngs in Rome, met friends who were in Venice. Hot, dank, smelly but new to me, historic and less gruesome than Rome; saw pretty much all it had to offer in a couple days.
2d & 3d times - accompanying someone who insisted on visiting during other travel. The 2d visit in October was much better climate wise but overall impression of once and done remained. 3d time was just about stultifying, swore to not again be talked into it. If any future companions insist on Venice, I'll meet them in Florence afterward.

@ Seamus: Thanks for responding! Again, I'm very glad that my experiences were not like yours. And while I gave Venice 4 full days, I didn't have sufficient time to see or do everything I wanted to do there in that time -- and I travel hard! How much time to give it is, of course, a matter of interests and preferences; and time of year undoubtedly matters (I was there in October).

With a place like Venice, I think one question is how much one would regret not seeing it, even if some people have had negative reactions to it. As an example, I did not like Santorini, but can't imagine going to Greece and being in the area and skipping it, and even though I didn't like it, I did greatly enjoy a few things and have no regrets about having visited it -- how else would I know whether I liked it or not?

I much prefer Venice to Dubrovnick which to me is like St Marks square on steroids. Only have visited Venice in the off season last 2 or 3 times as I am sure I would enjoy it less in the summer these days.

I've been to Dubrovnik once. I would consider old town Dubrovnik a "must see" as it's an amazing place but it's like a big museum. I've returned to Croatia and will do so in future but will not seek out a return to Dubrovnik. I've seen it. Less of an "experience" and more about "sights".

I've been to Venice a few times and was not entirely enthusiastic for my first visit about 20 years ago. The cynic in me thought it would be overrated and like a museum. If you have to compare Venice to Dubrovnik, I would say that Venice has much more "real life". I was wrong. Lots to experience in Venice. Not just sights. Not just a museum. It's also very large and easier to get away from the crowds than I would have originally thought. I have not been there during very bad floods (one visit did have some flooding) so I can't really comment on that.

Anyway, anyone visiting either Dubrovnik or Venice must obviously be prepared for throngs of crowds and anyone who can't or doesn't want to deal with crowds and "extreme tourism" in just about every way should think about going somewhere else instead.

Venice doesn't usually suffer from flooding. The "acqua alta" is an unusually high tide, which get pushed by strong southwest winds, and is also affected by changes in atmospheric pressure, which causes oscillation of the water. It can happen when it hasn't rained at all, and on sunny days. Like all high tides, it only lasts a few hours, and only affects the lowest parts of the city.

It's a complicated phenonomen, and the above description is very simplified. The practical information is that acqua alta almost never happens in spring or summer. An acqua alta of 110 cm above normal is enough to bring out the wooden walks in Piazza S. Marco. In recent decades, this happens about six times a year. Here is the distribution by month.

Attachment 1493

In the past 56 years, there has never been an event of this level in July or August, and only twice in May or September. It's most likely to occur in November, but even then it's only happened 92 times in 56 years, or less than twice in an average November.

Yesterday's acqua alta was the 4th highest ever recorded.

In recent years, it''s been happening more often. Venice is sinking and the sea level is rising.

I don't know how you guys can even think of equating the two cities.

Venice is in totally a different league. It's one of Europe's grandest cities.
It was the most important financial and maritime power during the Middle Ages and the Renaissance.
It's filled with palaces, churches, museums and art galleries...

Dubrovnik is a one-day city at best. It feels more like a medieval theme park than a real destination.
It's actually very short on things to do and see, that its main attractions are day trips to nearby islands.