Well, I would certainly recommend visiting the Apuseni mountains. Definitely not touristy and very beautiful. Also, in terms of towns, Cluj is very nice, also Sibiu. In Hunedoara there is a very nice castle, The Huniads Castle. While in Brasov, you could have a look at the Bran Castle (touted as Dracula's place, which is obviously not).
If you do have time to go to the Southern part as well, then the Danube Delta would be awesome. For Black Sea I would recommend Vama Veche or 2 Mai. Give me a shot when you're around / near Bucharest and I would be glad to show you some nice places to eat / have a good coffee in town. Enjoy your ride :)
Thanks so much @dragosroua :) That's a comprehensive list of destinations. Must tell you I got really excited while reading your reply! I also did a quick projection with google maps and the trail looks amazing :)
Yes, it looks really nice. A short correction, though: by Cluj, I meant Kluz-Napoka, as it is on your map. I don't know from where that "Cluj" city popped on your map, but believe me, it's not there :).
So I think the real Cluj (Kluz-Napoka) will come before Apuseni.
Enjoy :)
Thanks for the revision @dragosroua :) It seems like a pretty mountainous area over there...
That steep hill in the middle is located right before the city of Kluz-Napoka :D
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