This holiday season, many subway riders got the chance to ride vintage trains as part of the MTA’s Nostalgia Train event. As if riding a train from the `30s wasn’t cool enough, they included several retro advertisements in the cars. Particularly of interest was a series of ads called “The Subway Sun.” Much like today’s “SubTalk,” The Subway Sun was a series of public service ads that ran from the 1940s to the 1960s. Frederick G. Cooper was the original cartoonist behind the series, and in 1946 his protégée Amelia Opdyke Jones or “Oppy” took over and continued to design them for the next 20 years. The term “litterbug” is said to have originated from Oppy’s posters. Below is a collection of Subway Sun posters snapped on the Nostalgia Train.