It's about two hours, half an hour both ways and one hour at the fort. I am in total agreement with a previous poster, for a real Civil War enthusiast, an hour was not nearly enough time.
Once you board the ferry, there is a 30 minute ride to the fort. Then you'll have an hour to tour the fort (not enough time). Finally the return trip takes 30 minutes. For a total of 2 hours.
Approximately two hours, including an hour on the island.
About 2 hours...
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