One of the weirdest was shooting photos when a track side door opened, a man in a nice suit walked up to us, didn't say a word, smiled and shook our hands, each in turn, in total silence. He then revealed himself to be the chief engineer of the line 1, was happy to let us hang out and watch the trains with him, and said in parting.. oh, I really should get around to fixing that ingress point of yours..

Or a worker we bumped into who said he knew we weren't painters because we didn't throw rocks at him, and thanked us kindly.

The most surprisingly was stumbling upon a 1930s train, the Sprague Thompson in mint condition, hiding in a section of metro that we'd overlooked for years...