I have been to Croatia and stayed in the coastal town of Cavtat, about 30 minutes by car south of Dubrovnik, close to the Montenegro border. Whilst I did visit the island of Brac, I cannot whole heartedly recommend it.
If you were to choose only one island, people in the know would definitely recommend the island of Hvar.
It is regarded as the queen of the Croatian Dalmatian islands. It has been famous since the antique because of its important strategic and nautical position, the rich of the various historical periods, the culture and natural monuments and the literature.
Thanks to the mild climate, the warm winters and pleasant summers Hvar receives many guests, scientists and travellers, who are attracted by the dense mediterranean nature, rich tradition, architecture, and nightlife.
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