Walking the streets of an unfamiliar city is one the great pleasures of traveling. Sure you always go see all the sites that make it famous but if possible try to leave time for a walk or two or more. We look at a map, pick a spot, take some form of public transportation out to it and spend the day walking back to our hotel. Amazing what you will find(once found a book store with a stream running thru it). And always bring a camera, nothing large and heavy. If possible a mirror-less or a high end compact. If you have a DSLR leave the heavy zooms in the room just bring a small prime lens, something around 35 - 50mm. You really don't want the weight for an all day walk. I've carried everything from medium format to large DSLR's to pocket cameras, trust me lighter is better. You are more likely to make more images if you aren't tired from carrying a heavy camera all day. And there are images out there, images are everywhere! Walking over the Seine after an all day walk through the streets of Paris.