Serbia never stops amazing me with its natural diversity. The southern part of the country is more mountainous. A national park with the rather unassuming name "Stara Planina" has been sitting in my bookmarks for ages. Finally made it here (:

Turns out the rest of the world calls these mountains the Balkans. And that's actually where the peninsula got its name from. According to one theory, the Bulgarians started using this name about 1500 years ago, borrowing the word "balkan" from the Turks. It literally means "mountain."

What looks like a river in the photos and videos is actually a lake. I didn't believe it either, even when I saw it myself. I only managed to convince myself by looking at a map.

Along the way, I stopped by Nishava Gorge. A railway line runs through the mountains there (and it's still operational!). And part of the hiking route (an officially marked trail with all the proper signs) goes right along it. Including through a pretty long tunnel. Not entirely sure how you're supposed to deal with trains passing through.