The wall wasn’t destined to become an artifact when it was drawn in 1976. Instead, it was created spontaneously in under 30 minutes. Although Costello’s opened on the corner of 44th and 3rd, it would relocate three times mostly within the span of a block, before settling at its final address, 225 East 44th Street, in 1974. It was here that the bar’s owner, Timothy Costello, wanted new art to accompany the Thurber murals, which had become famous showpieces of the saloon, so he enlisted the help of Bill Gallo, a Daily News cartoonist. But Mr. Gallo didn’t want to compete with Thurber’s simple, witty cartoons drawn on beaverboard panels. So he proposed to Mr. Costello something of a stunt: “You close this place up for 24 hours and offer up free drinks and food, and I’ll get the best cartoonists in the country to paint your wall,” he said. Thus, that spring, 30 or so of America’s best-known cartoonists gathered to doodle their signature creations in what later became the Overlook.

Image Timothy Costello, the bar's owner, right, with John McNulty, a writer with The New Yorker, in 1946. Credit... Cosmo-Sileo

Mort Walker, the creator of the comic strip Beetle Bailey, recalled the spectacle in a 2004 interview: “I did my part, climbed up on a ladder and drew my character. Then I got down and had some drinks, so I don’t remember too much after that.” (Mr. Walker died in January.)

Sergio Aragonés, who is now 80 and still draws for Mad magazine, remembered the experience. “I got a beer and started drawing,” he said. “I thought up my cartoon right on the spot.” Mr. Aragonés added: “All the cartoonists still lived in New York at the time. We would all try selling our cartoons to magazines on Wednesdays and we would meet at bars like Costello’s afterward to drink and talk. There was lots of camaraderie. This mural represents a community that is no longer around.” Mr. Aragonés now lives in Ojai, Calif.