You definitely need to stay more than a day, we stayed one day and it wasn't enough. The swimming was a treasure, make sure you take those thin shoes to walk in water and snorkel! Teeming with wildlife due to the rich volcanic rock and vegetation.
It is a very small island and it takes about an hour to get there, so if you have a short holiday, it probably isn;t the best idea to go there. Try to get your ticket in advance as we did it on the day and could not find the ticket office for ages and missed the early hydrofoil!
Stunning island, lovely food, really quaint and pretty town and excellent snorkelling/diving opportunity.
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