4. Graffiti by Construction Workers is Hidden Under the Walls
In a 2013 behind-the-scenes visit Untapped New York took into the construction of 1 WTC (all the way to the 90th floor), we found a plethora of fun graffiti all over the walls by construction workers. There were manifestos, signatures, philosophical inquiries, and even a Garfield. They were on concrete walls and wooden floorboards — and inevitably remain today beneath layers of paint and drywall.
There were references to Descartes, Victor Hugo, Socrates and more, and an ongoing battle between groups — one which accused the other of defacing artwork.