Here are a few suggestions for your next trip from Koper

In 3 hours, you can reach Laibach, Rijeka.

In 4 hours, you can reach Kranj, Celje.

In 5 hours, you can reach Marburg an der Drau.

In 6 hours, you can reach Zagreb, Graz.

In 7 hours, you can reach Mailand.

In 8 hours, you can reach Rom, Turin.

In 9 hours, you can reach Wien, München, Linz.

In 10+ hours, you can reach Berlin, Paris, Budapest, Warschau, Stockholm, Prag, Brüssel, Amsterdam, Bratislava, Zürich...