I cannot say enough about our guide, who's name I have sadly forgotten. We took the tour on Wed., September 7, 2022, so if our guide is reading this, my apologies! We were the couple from Canada; the only other two people on the tour were from Portland, Oregon. Our guide was a walking encyclopedia of information pertaining to the NYC subway system.
We learned how the subway came to be, and what came before it, who built it and the battle between "new" and "old" NY money, which is a common theme in the HBO series "Enlightened". We learned how different lines were built by different investors, and how they eventually combined to become what exists today. We learned that the original City Hall station was/is extremely opulent, with skylights, tile, coloured glass tile work and brass chandeliers.
Sadly, it is closed to the public, but you can view it by 1) Becoming a member of the New York Transit Museum; and 2) Submitting government ID at least 72 hours before the date of the tour. I wish we lived in NYC because I would jump through these hoops to see it; the photos that our guide showed us were spectacular.
Even though we could not see the original City Hall station, we were shown tile work and tile pictures on various station walls that have significant historical meaning. We were also given tips on what to look for when riding the MTA. We highly recommend this tour.