A few years ago my daughter was in Calgary Canada on holiday and tripped on the pavement, fell over and broke her arm and damaged her teeth. Another pedestrian called for an ambulance which duly came, but before they would put her in the vehicle they had to have an imprint of her credit card. Yep, laid on the ground trying to get a card out of her handbag whilst the "morons" stood waiting.
The hospital treatment though was first class, as you would expect !
So I think Victoria the answer to the question that you pose is that if you leave these shores a credit card is your financial passport, especially if your heading to North America. Also the usual ten million pounds worth of holiday insurance is a must too!