In Cuba, cash is an absolute necessity. If you're from the United States, you will be completely unable to use your debit and credit cards — and that includes pulling out money at ATMs. Travellers from other countries don't have the same restrictions but should still have ample cash because that is what is mainly used by Cubans. Plan ahead and bring more money than you think you'll need, because once you run out, you're out for good (if you're American). Stash cash in several places to ensure you have backup if you need it.
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