There was no ATM at the airport and banks were closed. If I missed this flight, all my subsequent flights would have been cancelled

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I was 19 and travelling by myself for the first time. It was 1994 and departure tax wasn’t always part of a plane ticket, so it sometimes had to be paid before flying out of a country. And if you didn’t have it, you didn’t leave – something I was about to learn the hard way.

I was on a five-week trip around South America that I’d spent years saving for, visiting the pen pals I’d written to as a teenager. At the airport in San José, Costa Rica, I was waiting in line for customs when I realised the border guard was asking those ahead of me to pay US$5 in departure tax – money I didn’t have. It doesn’t seem like a lot now but it was back then. I’d flown in from New York’s JFK airport two days previously and the only ATM had been out of order, so I hadn’t been able to get cash out there, and I’d spent my remaining few dollars on an overnight stay in the city.