Those heading north on North Broad Street see the vertical graffiti spelling out the words so large that they are visible from Google Maps: “Forever Boner."

Turning around, from the south, the words are flipped: “Boner 4Ever."

Towering over Broad, the imposing Art Deco building that housed the National Bank of North Philadelphia, listed in the National Register of Historic Places, is best known to Philadelphians for this public art.

Redevelopment plans for the building, which many consider a Philadelphia landmark, to become a Marriott hotel have moved people to express sadness and outrage on social media that the promised “Forever Boner” would come to an end.

But the developers for this project are aware of the significance of this graffiti. The interior designer wants those distressed residents to know it is too soon to lose hope.

“We have had ‘Boner Forever’ on every presentation we make. I’m not kidding,” said Floss Barber, CEO of Floss Barber Inc. and the project’s interior designer. “It’s so important to the building. We’re incorporating it into the overall project in various ways.”

It is premature to say exactly what role this famous Philadelphia art could play in the design, Barber said, noting she has not contacted the artists yet. But, she said, her team is brainstorming options: A mural? Wallpaper? Art? Sign on the roof deck? Removed from the building’s exterior or not? These are all suggestions she said the company is working through before making formal proposals.

The building is formally called the Beury building, named after Charles Beury, the first president of the National Bank of North Philadelphia and a former Temple University president. But for the last several decades the building has been vacant.

During that time, graffiti artists have made their mark. Legend has it that this most-famous graffiti is the work of two separate artists, one known for tagging “Boner” or just the signature "B" in various locations, and another known for tagging “Forever."

The Beury Building is possibly the most-famous graffiti collaboration in Philadelphia.

The artwork even earned national fame over the summer. During the hours-long shootout between a man armed with an AR-15 assault rifle in a North Philadelphia home and police, national news outlets directed their cameras to the neighborhood. Standing tall in the split frame on CNN of Wolf Blitzer and Broad Street is the easily readable message: “Boner 4Ever.”

Brian Murray, the co-founder of Shift Capital, the company that bought the 14-story building in 2012, called the “Boner 4Ever” tag “urban lore in North Philadelphia."

When asked if that marker would remain on the building, he said: “We are figuring out a way to appropriately pay homage, but I don’t have any immediate responses to that question yet.”

Murray said they hope to break ground this year. Inquirer architecture critic Inga Saffron in an October column detailed the plans for the building, which she called “a sort of lighthouse,” and said the forthcoming development in the area shows "the city is finally getting ready to give the community hub at Broad and Erie the attention it deserves.”

But it will be a while before the hotel is up and running. Mihir Wankawala, CEO and founder of the Wankawala Organization, which is partnering with Shift Capital on the project, said they are aiming for the hotel to open in the fall of 2022.

“We want to preserve the historic elements of this building, the ‘Boner 4ever’ sign for sure,” Wankawala said. “We definitely want to incorporate those elements of the building, but we haven’t settled on how we are going to do it yet."

If you are or know the artist(s) behind “Boner” or “Forever,” contact reporter Ellie Silverman at esilverman@inquirer.com or 215-854-5104.

Staff writer Oona Goodin-Smith contributed to this article.