The above image shows a sculpture in Manhattan memorializing the Staten Island ferry disaster of Nov. 22, 1963, when an entire ferry full of people was pulled beneath the saves by a creature with giant tentacles. The terrible tragedy is usually blamed on a gigantic octopus, but readers of H.P. Lovecraft or Illuminatus! probably have a more clear idea of what really happened. It's been explained that you've never heard of this because news coverage was overshadowed by the assassination of President Kennedy on the same day. See this "documentary."
Via the 2019 Advent Calendar of Curiousities, which I found out from RAW fan Mark Frauenfelder in the Recomendo newsletter.