Flew into Zagreb. Drove to Slovenia, then drove to Bosnia through Croatia. Then back to Croatia for the night. Went to Dubrovnik for a while, back to the hotel. Then back to Bosnia for a few hours the next day, onto Montenegro to play disc golf. On to Kosovo, then to Albania and into Macedonia. Then back through Serbia to Croatia. The goal is to visit every country in the world, this was part of Europe we'd never been to. Bosnia was pretty, much better than expected, same with Serbia. Croatia is fucking wow. Likely wouldn't hesitate to spend a little more time in any of the places we stopped into.
Edit: I think this is 77 or 78 countries so far.