That the Beatles released Ticket to Ride. At one point in my life I lived this song with all its lyrics stuck on permanent replay in my head. Knew it well. But then Wiki mentions that its title was a reference to Hamburg prostitutes. Huh? Maybe I didn’t know it so well.
“While the song lyrics describe a girl “riding out of the life of the narrator”, the inspiration of the title phrase is unclear. McCartney said it was “a British Railways ticket to the town of Ryde on the Isle of Wight”, and Lennon said it described cards indicating a clean bill of health carried by Hamburg prostitutes in the 1960s. The Beatles played in Hamburg early in their musical career, and “ride/riding” was slang for having sex.”
From Wiki.