Getting to Brac island by ferry is the cheapest and the fastest way. This island is only 7 nautical miles from Split. Jadrolinija runs the ferry service between Split and Brac.
The closest ferry port is at Supetar, on the island’s north coast, almost directly opposite Split. It takes just over an hour to make the crossing. (costs 27 HKN).
During the lower season there are more then seven times a day, while in the high season the service runs pretty well, with more than 15 crossings, the first one at 06 am and the last one going at about 1 am.
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In case you need more information, dont hesitate to ask.