This how I do it:
1. Study the picture in question for anything specific to the subject/area. A sign, a peculiarity of any kind. Something that you wouldn't find just any/everywhere.
2. Go to
Google Images.
3.
Type words into the search box. As I said earlier, for V's pic I typed "steel bridge Washington state", (I first typed "steel girder bridge Washington", but that didn't do the trick for me) without the quotation marks, and just drilled down the results til I found one that was similar. I then clicked the link for that image, and, after finding some sort of identifying info, double-checked it against Wikipedia.
4. Lather, Rinse, Repeat.