Sorry, I did not intend to sound insulting. My apology for any offence.
I was just trying to illustrate the point so it was easy to understand, I got the impression you had difficulty grasping the idea.
There are no end of photos available on the web. Some paid for, some free. For free ones there are many threads here already mentioning sources, just search “free photos” or similar to find those threads. Or try a Google Image search, filtering for those labeled for reuse.
https://www.google.co.uk/search?q=golden+gate+bridge&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAWoVChMIpanIjZauyAIViQMaCh2-xQte&biw=1330&bih=923#q=golden+gate+bridge&tbm=isch&tbs=sur:fc