I was in Croacia last summer. It was a very pleasant trip. I was there with three friends, and all of us thoroughly enjoyed it.
Our trip started at Renfe North Railway Station, because we had to take a plane from Barcelona to Dubrovnik. We visited the main cities in the Croatian coast, like Pula, Zadar, Split and Dubrovnik, but we were in Sibenik and Biograd as well. The last two cities I have mentioned are very peaceful places, where you can spend your free time meeting many people, very friendly people.
Croacia is a very safe country for the sightseers, maybe because they want to recover one of the most important engines of their economy, which is tourism. We always were walking peacefully everywhere, and people were very attentive with us, well, with every sightseer.
All places are very good, but the most beautiful for us was Pula, a city where you can see the influence of the Roman Empire, and a place named Pletvice Jeretza Lakes, a large unspoilt national park. Zadar and Split are cities nobody should forget to visit, but the most popular city among tourists is Dubrovnik, where the Old Town shows you what it was like to live in the Middle Ages and you can enjoy a lovely night with people from all over the world. I recommend you to visit an island, because in one of them, in Lopud, we could enjoy of a Caribean beach, I swear.
I hope you enjoy your trip to Croacia as much as I did.