We stayed a total of five nights in Bol, and included a visit to Supetar.
Brac island is a very picturesque island with a quiet way of life. From what I understand, its neighbor Hvar is more busy, as it is a party destination. The reason behind choosing to have our vacation on Brac was because were intrigued by the idea of staying in a small village without a whole lot of attractions that are "obligatory" to see and do. Bol proved to be a quiet town, especially in the daytime when the tourists are on the beach. Even in the evenings, Bol is rather quiet compared to other popular destinations in the southeastern/southwestern Europe, and never once did our stress level increase. However, we visited in what's considered the low, or medium season. You can not expect Bol to be quiet when the high season kicks in, and the amount of day tourists increase. Our host said that numerous boats travel to Bol, so that the tourists can visit Zlatni Rat, and that this makes Bol a rather busy, and stressing town even in the daytime.
Would I recommend Bol? Definitely, if you travel in the low season, that is. Not only will the town have a quiet vibe, but the beaches surrounding Zlatni Rat will be almost empty. Now that's relaxing.
As for Supetar, we just went here so that we could do something else for a change. From what I gather, it's slightly larger than Bol, more touristy, but doesn't necesarilly offer more in terms of activities (apart from water sports). Not really worth it as a day trip, in my opinion, although the bus ride to and from is rather nice.
Go and visit Brac before it's destroyed by mass tourism.
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