Prague and the Czech Republic is extremely beautiful to visit. Prague is HANDS DOWN the best city in Europe. I've been to approximately 9 countries in Europe and I can tell you Prague was the most memorable. (I'm half Czech too, but I'm not rooting for it just because of that!)...
It's a very cultured city, and very rich in history. People are very nice there as well, and are very generous and kind to tourists, a lot more decent than other cities and countries.
You could also go to Pilsen (or Plzen), which is about an hour away I'd say...It's the second largest city in the Czech Republic, but not as "grand" as Prague is. Not many tourists go there though, I'm not sure why. It's just not as advertised I suppose. Outside of these cities are country roads and farms, it's extremely beautiful and picturesque.
Prague is a very romantic city too, the bridges are incredibly famous and beautiful. Many movies and music videos were filmed there, too.
hope that helps! I know if you went there, you will not be disappointed.
and did i mention many supermodels come from that country? *wink*...my dad found my mom in czech...lolol
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someone mentioned interlaken, switzerland. I've been there, during the summer. it's absolutely breathtaking. if you're more of a nature-type who enjoys nature-like views and hiking and doing outdoorsy things, interlaken is definitely a must.