Serbia vs Lithuania

Between the two, as is, I would select Belgrade but not for the same reasons but historical. Now to tweak the itinerary a bit, I would include Kleipeda as well as Vilnius, chiefly for reasons of historical significance, by choosing Lithuania. A tough call, even more so if Novi Sad is added to Belgrade. Krakow and Budapest have the best hostels to choose from, eg, Wombats in BP due to its facility and prime location, and the Greg and Tom in Krakow.

I haven't been to Belgrade or Vilnius, but I have been to smaller towns in each other country you're visiting and (as usual) found that they increased my appreciation of that country. Smaller towns may be better preserved and prettier because nobody needed to build a new office block in the middle. They can also be cheaper, friendlier, easier to navigate, etc. And shorter hops means less transport expense.

I liked both Belgrade and Novi Sad. If your time in Novi Sad is limited, consider taking a bus from the train station to the historic district, as it is about 1-1/2 miles.

My vote goes clearly to Vilnius. The description of "an exsplosion of Baroque" is particularly apt. It reminded me of what Prague would look like if it had 1/10 the tourist traffic and 1/100 the souvenir shops. The food is also delicious, although I nominate Lithuania for making the worst beer in Europe.

I was in Belgrade in the early 2000s when, quite frankly, the country wasn't at it's best. I found the atmosphere kind of oppressive at the time, but perhaps things have improved.

Hello. I’ve been to Vilnius and Klaipeda three times, but not for a couple of years. However, like others that have been to one or the other but not both cities, I haven’t been to Belgrade. Vilnius will have the things you listed and more—wonderful cathedrals, Jewish sites, a museum in a former KGB building, the TV tower infamously attacked by the Soviets in 1991, and so on. Klaipeda is about 4 hours from Vilnius by bus; less by car. It was a part of Germany, but there aren’t a great many places of interest to tourists. Enjoy your trip.