The Sistine chapel of comic-strip art

“And there’s Fred Flintstone,” said his friend, Marcel Alers.

“I grew up with all this,” Gold added. “My kids are in their 20s and probably have no clue who these characters even are. This is my childhood.” The crowds remained focused on the glowing television screens and the Buffalo wings.

This crumbling, beer-splotched wall in the back of a sports bar on East 44th Street is one of New York’s more neglected cultural treasures.

Created in the 1970s, it is a veritable Sistine Chapel of American comic-strip art: the 30-some drawings across its face were left by a who’s who of cartooning legends, including a Spider-Man by Gil Kane, a Beetle Bailey by Mort Walker, a Dondi by Irwin Hasen, a Steve Canyon by Milton Caniff, a Hagar the Horrible by Dik Browne, and a Dagwood Bumstead by Paul Fung Jr.

There’s also a self-portrait by Al Jaffee, a doodle by Bil Keane, and a Mad magazine-style gag by Sergio Aragonés.

Old regulars are familiar with the wall’s past, and comic book scholars make occasional pilgrimages to the bar, but the Overlook’s cartoon mural remains largely unknown and untended.

Al Jaffee, 97, was surprised to learn the wall still existed when reached by phone at his apartment. “I’m amazed to hear it is around in this crumbling state,” said Jaffee, who created Mad magazine’s signature back-page Fold-In feature. “We did that stuff a long time ago. I’m curious myself how many of us who worked on that are still around. I was honored to draw it alongside so many of my heroes.”

Mark Evangelista, an owner of the Overlook, said his attempts to bring attention to the artifact have been futile. “No one cares,” he said. “I’ve tried telling national cartoon organizations and societies about it, but no one is interested. This bar could be like McSorley’s if only more people knew about it. This is a piece of New York history.”

Long before the back wall of the Overlook became the fading wallpaper of an anonymous sports bar, it was witness to a glamorous era of literary celebrity when the establishment was the site of a storied bar called Costello’s.

The dark Irish saloon, which opened as a speakeasy in 1929, was a beloved haunt for journalists and writers. Sitting in the shadows of the screeching Third Avenue el (the elevated train line that ran through Manhattan until the 1950s), it was narrow and lined with booths, and a mirror was taped with currency from visiting foreign correspondents.

The place sprouted barroom tales: Ernest Hemingway broke a walking stick over John O’Hara’s head, and the shattered shillelagh was hung from the ceiling; Marilyn Monroe received gruff service when she ordered a vodka screwdriver from an unimpressed waiter; celebrated humorist James Thurber drew murals on the walls of the saloon to pay off his Depression-era bar tab. Writers for The New Yorker like A.J. Liebling, Joseph Mitchell, Maeve Brennan, and John McNulty also made Costello’s their canteen. (McNulty, who liked steak sandwiches and gin for lunch, honored the bar and its colorful characters in numerous dispatches for the magazine, always referring to it as “this place on Third Avenue.”)

The wall wasn’t destined to become an artifact when it was drawn in 1976. Instead, it was created spontaneously in less than 30 minutes. Although Costello’s opened on the corner of 44th and Third, it would relocate three times mostly within the span of a block, before settling at its final address, 225 E. 44th St., 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 Gallo didn’t want to compete with Thurber’s simple, witty cartoons drawn on beaverboard panels. So he proposed to 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.

Mort Walker, 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.” (Walker died in January.)

Sergio Aragonés, 80, who 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.” 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.” Aragonés now lives in Ojai, California.

The wall is a genuine time capsule. Bursting with zaniness, it is filled with dated humor and antiquated references: cartoon characters hoist martini glasses and tell bawdy jokes through word bubbles, an Aragonés scene features sombrero-wearing banditos with bulging eyes ogling a maiden, and a caricature of Abe Beame depicts the former New York mayor as haggard and waving a beggar’s cup (presumably in reference his shabby re-election prospects that year).

The cartooning in comic strips and comic books in the 1970s wasn’t the American art form it is considered today. Vincent Zurzolo, a co-owner of Metropolis Collectibles and ComicConnect, speculated that the wall might be worth as much as $50,000. “It definitely has monetary value,” he said. “If there is a way to safely remove the wall, then a big institution might go for it and buy it. Something like this is one-of-a-kind and cannot be replicated.”

Jaffee, who couldn’t precisely recall what he drew in ’76, addressed the wall’s value wryly. “The scribblings on the caves in France also became more important in recent times than they were in their own times,” he said.

Costello’s finally closed in 1992, and the wall has survived through luck since. A dive called the Turtle Bay Café first replaced Costello’s. Baby-blue wallpaper and happy-hour specials appeared, but the wall was left alone.

It shuttered in 2004, and there were fears the space would be stripped to make room for a fancy restaurant.

A few activists cried for the mural’s protection, but their cause gained little notice. The wall was saved instead by the arrival of the Overlook, which leased the space, and wasn’t interested in heavy renovations, although Evangelista admits he didn’t know what to make of the wall at first. “When I initially saw it I was like, ‘Let’s just get rid of it,'” he said.

But he soon learned of its past. “Some old-timer came in one day and told me, ‘You know this used to be Costello’s, right?'” he continued. “Then I went online and I saw the photos. I did my reading. I discovered I have a piece of New York history here.”

Evangelista, who grew up in Queens and aspired to become a police officer, has become the wall’s proud steward since. “The wall is safe as long as I’m here,” he said. “If we leave, it will probably get gutted. But I won’t let that happen here until I drop dead.”

He paid tribute to the wall in 2005 by gathering a group of the surviving cartoonists to draw a new mural in the dining room. Bright, clean, and with more wholesome humor, it will never be confused with the original.

A mystery also remains: the James Thurber murals traveled to the final Costello’s address and remained there, but they disappeared sometime in the 1990s, and what exactly happened to them is unclear. Some suspect that Costello sold them, that The New Yorker claimed them as office art, that they got accidentally painted over, or that they were outright sliced from the walls and stolen. “The legend I heard is that a Costello’s bartender took them,” Evangelista said. “I heard they could be worth a million bucks.”

Rosemary Thurber, 86, who manages her father’s estate and could remember visiting Costello’s with him, also could not account for the missing drawings. “I do not know what happened to them,” she said. “I don’t think any of us does. Maybe someone will eventually find them in some deep dark basement.”

At the Overlook one recent afternoon, construction workers and businessmen knocked back beers. These days, the focus is the television, not the wondrous relics from the Costello’s era hidden around the building: a metal cash register, a tin ceiling, rusty filing cabinets, a set of fluorescent lights, a tall safe with a combination dial.

Evangelista pointed these out proudly, noting that legends like Ernest Hemingway and Arthur Miller probably once used his bathrooms. He poured himself some whiskey in front of the wall and toasted the cartoons. “Here’s to drinking in a literary bar,” he said.

Midtown happy-hour crowds soon filled the Overlook. Among them was Ray Hess, 69, who is one of the bar’s longtime regulars.

A few decades earlier, he frequented Costello’s as a young man and got to see the mural in its pristine state. “This wall is just legends and stories now,” he said.

“But it defined a time when the writers and newspaper people and artists got together here. And when they did, they made the flavor of the world change. This wall is what came of that.”

He noticed the drunken scribbles and beer stains left by customers along the mural. “The years have caused it to dim,” he added. “But that’s not just the wall. That’s life in New York City.”

This article originally appeared in The New York Times.