I found the metro in Paris to be an amazing bountiful place for candid and street photography, and there is such a wealth of visual stimuli going on around every corner!
One of my favorites was shooting from across platforms, people were pretty involved in watching and waiting for their trains that they were totally oblivious to my presence. So I got so do my voyeur thing quite anonymously and efficiently, as they posed so perfectly for my camera.
I noticed (this trip in particular) that people in Europe don’t really try and make eye contact on public transportation with strangers or try and start a conversation with you like folks in the USA would, this definitely makes taking candid portraits a lot easier… Which in turn makes my fly on the wall style photography so much more effective!
Technical stuff: Fujifilm X-Pro2, 50mm XF f2 R WR lens, 1/250th of a second @ f2 shot at 2500 ISO