The Old Town Bar celebrated its 125th anniversary on Sunday. View Full Caption Amy Langfield

UNION SQUARE — Oh, how New Yorkers love to fight over what’s the best this, or the oldest that. And it seems there’s always a new nugget of information turning up to make things even more interesting.

Such is the case with the origin story of Old Town Bar, one of the city’s oldest watering holes, which celebrates its 125th anniversary this year.

The doors opened at 45 E. 18th St. sometime in 1892, and legend has long held it was first known as Viemeister’s, a saloon serving beer from one of Yorkville's German breweries.

But the current owners now think Viemeister’s actually opened later, in the 1910s, with the latest evidence now taped to a mirror behind the bar.

“We have come to a fuller understanding of the Old Town over the years,” said Gerard Meagher, the storied establishment's current co-owner.

It appears Viemeister’s was predated by L.E. Reichenecker Cafe, and before that it was Burckel Brothers’ Cafe, the bar that likely opened in 1892.

A Burckel Brothers' Cafe business card (DNAinfo/Amy Langfield)

Many of the bar's iconic fixtures date to those early days, including the 90-foot mahogany bar, possibly the city's oldest operating dumbwaiter, and of course the men's downstairs urinals, which got their own centennial party in 2010. (The women's restrooms remain upstairs, the only part of the bar where women were originally allowed, Meagher said.)

Other celebrated features came later, such as the booths with Prohibition-era hiding places under the seats for bottles of booze. The walls are lined with relics and pictures of celebrated writers who frequented the bar, artists from Andy Warhol's Factory around the corner, as well as movies, ("The Last Days of Disco," "Izzy & Moe" and "State of Grace,") TV scenes (David Letterman's opening credits) and music videos (House of Pain's "Jump Around,") filmed inside.

But it's the photocopied paper hanging behind the bar that offers new clues to the very start. It shows a slightly tattered "Burckel Brothers’ Cafe” card touting its “business men’s lunch served from 11 to 3” at "45 East 18th St. bet. Fourth Avenue and Broadway." In the top corners, it bears the names M. Burckel and A. Burckel and the telephone number "4210 GRAM." In lighter ink, there is a stamp for L E Reichenecker.

“About five years ago, we were contacted by Peter Heim, who had found a card when his grandfather died that had his great-great grandfather L.E. Reichenecker on a card from the Burckel Brothers Cafe then later a card with the premises called L.E. Reichenecker Cafe, so I suspect that he acquired the cafe from the Burckels,” Meagher said.

Also behind the bar is a framed, city-issued saloon liquor license (No. 3262), for 1895 to 1896, back before the state took over alcohol permitting.

Gerard Meagher, co-owner of Old Town Bar, holding the venue's 1896 saloon license. (DNAinfo/Amy Langfield)

“The 1896 liquor license has Jacob Burckel on it,” Meagher noted. That item was acquired from a bar historian who found it in the NYC Municipal Archives, Meagher said.

Other items offer even more clues.

"We have a pack of matches from when the Old Town was Craig's Restaurant during Prohibition that says 'Formerly Viemeister’s,'” Meagher said. "We assume it became Viemeister's after L. E. Reichenecker's cafe.”

This past Sunday, Meagher, his family and longtime friends of the bar gathered to celebrate the 125th anniversary.

So does that mean Sept. 17, 1892, was the day the bar first opened, Meagher was asked shortly before the festivities began.

“We have no idea,” he said.

READ MORE: Old Town Bar Owner Talks About The Classic Tavern's 125th Anniversary