It's so sad to think of the inhuman things people did to others, and a visit to this island makes it so real. You'll need a passport to get ferry tickets, and the ferries are packed before they ever depart. Definitely worthwhile to do a pre-arranged tour to help you navigate the ferry and to truly understand the history of the island. Plenty of tourist shops and small cafes/restaurants. You can do this tour in as little or much time as you like. The ferries return frequently.

Visited (and stayed one night) as part of a tour. Short ferry ride (always fun on a ferry eh?) from Dakar port. Small population reliant on tourism (mainly day trips) and fishing. One can see many reminders that this was one of the major embarkation points for the slave trade run by numerous European countries . The day we went (Monday) the museum was closed . The are some interesting memorials. As well as the history of slavery, one can see ,on the hilltop ,the gun emplacement that was the rangefinder for the Dakar batteries in WW2, when the Vichy administration were in charge and the Allies and the Free French attacked to try and take control of the port (but lost the battle and ships)

This is must be one of the most stunning places to visit in Africa. A 20 ferry ride from Dakar and you are in another world, transported to the Mediterranean. Beautiful buildings with stunning narrow passageways and such an interesting history. The real history may not be the the official history but the sentiment is still correct. Easy to spend most of the day here but you should arrive early.