In June, getting a passport became mandatory for Americans traveling to Canada, Mexico or the Caribbean via land or sea. However, there is an exception: You don’t need a passport if you are traveling to these areas on a closed-loop cruise, which is a cruise that begins and ends at the same US port.
Technically, all you need to go on a closed-loop cruise to any of these three regions is photo ID and a state-issued copy of your birth certificate or naturalization certificate to prove that you are a US citizen.
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