I don't profess to be any great expert on photography. I only have a point-and-shoot camera (but would really really like an SLR), and, reading books, looking at websites etc, I know I have a long way to go before my photos are any good.
All that said, however, I was reminded of a very important consideration while I was away over the weekend. So important (to me), I'm declaring it my number one rule for travel photography:
Always check the charge on your spare camera battery before you go out exploring a new city.
Here's hoping I remember it next time I go away...