Sorry this is yet another "what to take on my travels" thread but it's an easy one!
We're going on holiday to Egypt in a couple of weeks and we're planning a day trip to Petra while we're there.
This will be an organised sight seeing trip rather than specifically for photography and it's going to be very hot so I want to travel as light as possible.
I'll be taking my 30D with the 17-85 IS lens (only one I own!) question is, is there anywhere in Petra where I'm likely to need an external flash or can I leave that behind? Without the flash I should be able to get the camera & small accessories in my medium crumpler rather than the XL 

