Safety. It's pretty safe these days. But like any place, there are pickpockets. So we hide our valuables. The best method that I have experienced for keeping important valuables safe is in an additional pocket that hangs down your pant leg. A friend of mine made her own. It's simple to sew two sides of fabric together just wide enough to hold your passport, an ATM card, and a little cash. Then take a big diaper pin and pin it to the inside of your pants or skirt. It's always there, and you can settle your nerves as it's easy to check it with your hand.
I prefer this to a neck strap because, as a photographer, I don't need anything extra around my neck. It is also preferred over a waist belt which can be uncomfortable as it bunches and is not as easy to check.
These pocket passport bags can also be purchased online for about $20.
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