The enormous cockroach floats 24 feet above City Dock in Annapolis, where it has photobombed the historic waterfront as part of an ad campaign for years.

Ask why a billboard stands at the heart of Maryland’s state capital — a city that famously regulates rose trellises and replacement windows — and explanations come with a sigh of resignation.

“Political third rail. I’m serious,” said Wil Scott, chair of the city Historic Preservation Commission. “I hate the sign. I’ve always hated the sign. I’ve talked to all my aldermen. I’ve talked to all the mayors. Nobody wants to take it up.”

Until now.

Efe Brock, who says he grew up looking at the sign, asked city officials this week to cite its owners for violating historic preservation laws and the ban on billboards. He wants the city to force the owners to remove it.

“I would encourage the mayor to, if he has the gumption, to instruct his lawyer and city manager to take this complaint seriously,” Brock said.

In a town that cherishes and profits from its 380-year legacy, the billboard is — perversely — historic.

It is a remnant of the working harbor, planted on a lot where coal, brick and lumber once were stored. Those businesses put up signs on the spot, and they were replaced by a billboard sometime in the 1930s.

The late Robert Campbell, a one-time alderman, bought the billboard in the early 1960s and leased it to a company that markets it. Today, it’s owned by his daughter, Jane Campbell-Chambliss, and her husband, Peter Chambliss.

Four million people visit Annapolis every year, and tens of thousands walk or boat by the billboard on a pleasant spring weekend. Campbell once claimed the 300-square-foot sign was the most valuable billboard in Maryland.

Over time, it has been both mundane and controversial. Campbell used it to promote his auction house. There was that time a drunken sailor showed up in a Pentagon sobriety campaign. Balance that with the naked woman straddling a bottle of Courvoisier.

In 2018, the National Historic Trust named Annapolis one of America’s most endangered historic places, and local preservationists used the sign as a backdrop to share their concerns about new Mayor Gavin Buckley’s plans to remake City Dock.

Buckley crashed the event and offered to work together.

“The billboard is older than you and I,” said Robert Clark, president of Historic Annapolis at the time. “It’s part of the look.”

Today, Clear Channel Outdoor controls the sign. The dead cockroach is a pitch for a regular customer, Home Paramount Pest Control, that comes and goes.

“I hate it too,” Campbell-Chambliss said.

The city considers the billboard exempt from zoning rules because of its history. The roach is protected, too.

“We have no control over that, nor does anyone else,” Campbell-Chambliss said, “because it’s freedom of speech.”

Brock approached city officials in March, arguing that any exemption from the city ban on billboards — it’s the only one in Annapolis — and Historic District rules lapsed when lights were added and other changes made.

Tuesday, he presented a 13-page petition to the commission, punctuated with maps, photos, code citations and emails. One focus is a law that requires Historic District property owners to seek approval when their signs change size, shape, location — or content.

John Tower, the city’s chief of historic preservation, asked planning and zoning staff to review Brock’s detailed argument. The commission will examine the idea this month.

“I ask about this and talk about this all the time,” Tower told the commission. “And I don’t understand the law that’s kept this in place.”

If Brock can’t persuade the city, there are other reasons to think the time of the sign is running out.

Billboards have more competitors than just five years ago. Digital advertising might end the reign of Maryland’s most famous roach sooner than a drawn-out zoning fight.

“I think its days are numbered,” Clark said.

Brock is not an attorney. He’s that guy.

He’s the guy who researches the city code for ways to crack down on ads stuck to stop signs. He files public information requests on parking enforcement revenues to get something done about trucks blocking the bike lane.

He invests time and considerable intellect into his crusades.

Brock went to the City Council in January to talk about one of his concerns, but a discussion of another issue got him thinking about the billboard.

He listened as Historic Annapolis President Karen Brown argued that a proposed maritime welcome center at City Dock doesn’t fit aesthetically. It is part of a $100 million project to protect the Historic District from flooding, remove 150 parking spaces and replace them with an elevated green space.

It was approved over Historic Annapolis’ objections. The nonprofit challenged it in court, arguing the center should have been rejected as an illegal addition to a historic building included in the plan. Work began last week.

Brown’s testimony made Brock decide to compare the two sites, which are linked by Campbell-Chambliss. She sits on the board of Historic Annapolis.

The sign doesn’t appear in drawings of the future City Dock. It was intentional.

“I assumed that such a large billboard with silly commercial messages would be taken down sooner or later, once the City Dock Park is completed,” architect Bryce Turner wrote.

Some suggested using it to promote downtown events, while others see a space for public art or even a selfie background at the remade City Dock.

Campbell-Chambliss knows some see the sign as a blight. Maybe that’s why neighbors toss full dog poop bags onto her lot.

She’s started negotiations for a change, but won’t say if it is for the sign or the roach.

“What we’re hoping to do, I hope, will make people very happy.”