In a row of hotel rooms atop the Stud gay club South of Market, reporters are clacking swiftly at computer desks where beds used to be.

One is writing a story on a gay politician running for the state Assembly in Los Angeles. An editor is designing a page for "The Best of the Gays," readers' choice awards, and in the next room, a writer is compiling a list of weekend club parties.

If San Francisco is the national epicenter of gay culture, then the Bay Area Reporter newspaper is the pinpoint within it - the place to discover what matters most to the gay folks living within the most influential gay city in America.

This year, the BAR officially hits middle age.

After 40 years of covering what was then known as the gay liberation movement, from early police harassment, to political efforts to ban gay teachers, the City Hall assassinations, the AIDS epidemic and now marriage equality, the free weekly paper is taking a pause to celebrate its evolution as the country's longest continuously published gay newspaper.

"Five of the 10 gayest ZIP codes are in San Francisco," said Publisher Tom Horn. "All trends in the gay community emanate from here."

While most big cities now have a gay newspaper, no other paper comes close to the impact of the BAR, which began as a gossip flyer with bar advertisements and grew into the country's loudest voice for the gay community.

An exhibition at the Union Bank on California Street, coinciding with Gay Pride Month, highlights the newspaper's most memorable front pages, vintage photos and video.

Today, 100,000 people read the BAR each week, Horn said.

Although the Internet has killed its classified advertising, the BAR hasn't succumbed to the economy and the iPad like so many mainstream papers, in part because its display advertisers have remained loyal, as predominantly gay business owners want to reach customers who prefer gay doctors, therapists and bookstores. The paper has had no layoffs and is operating in the black, although its profit margin "is marginal," said General Manager Michael Yamashita.

All profits go back into keeping the business running. The BAR has 12 staff writers, yet 75 people put out the paper, including freelance writers, photographers, drivers and designers.

As a niche publication with a singular take that's hard to find anywhere else - the BAR has a long-standing transgender column - the paper has maintained its average 36-page size throughout the recent economic downturn.

It was that niche audience that the late restaurateur Bob Ross had in mind in April 1971 when he and business partner Paul Bentley mimeographed some stories and photos and delivered them to local gay bars.

Those early issues were dedicated to the events and drag contests of the local Imperial Court, along with listings of weekly bar parties and drink specials. The front page of the first issue was an invitation to "Come Meet All Your Friends at Circus Circus."

Community's power grows

But if the early copy was light, the paper's presence was a milestone in the growing political might of the gay community.

Life magazine had come out with a cover story in 1964, "The Secret World of the Homosexual Grows Bolder and Broader," naming San Francisco as home to 70,000 homosexuals, and inadvertently causing a migration.

The late '60s were marked by increasing rebellion against police raids of gay bars, most notably Stonewall in New York in 1969. A few years before that, Compton Cafeteria in the Tenderloin had its own riots over police arrests. When San Francisco police showed up with cameras at a black-tie gay charity fundraiser at California Hall looking to photograph "known homosexuals," many felt that things had gone too far.

"You had all these professionals, drag queens, and leather people with no common voice. So Bob thought the community needed a paper," Horn said.

Within a year, the paper was taking on weightier issues, covering Gay Alliance protests over discrimination in hiring, and relations with police. A front-page story in 1973 followed a municipal judge's decision that nude dancing was not illegal, and charges were dropped against the go-go boys at the Gaslight. When the gay Twin Peaks softball team bested the San Francisco Police Department team in 1974, the paper gleefully ran a banner front-page headline: "Police Beaten!"

All of a sudden, there was a classified-ad section for a gay audience. The paper wanted to support community businesses, people wanted to help gay customers, and customers wanted to patronize gay establishments.

"People wanted their doctors and lawyers to also be gay, because they wanted that trust. Readers became loyal to the advertisers," Horn said.

The personal ads were also a big hit. Reading them was a weekly activity, said state Sen. Mark Leno, who arrived in San Francisco in 1977.

"The BAR was a portal to my new home and community," he said.

It also unknowingly outed his secret summer romance, by publishing a photo of Leno and his partner at a race.

"What followed was the most glorious 10 years of my life," he said.

Harvey Milk's influence

In the '70s, a schoolteacher and camera shop owner named Harvey Milk began writing the Milk Forum, a political column that led the paper's coverage of state Sen. John Briggs' doomed initiative to ban gay public schoolteachers.

"Milk helped us realize we should take more seriously the opportunity to address issues in the city that were in crisis," Yamashita said.

When the Briggs Initiative was voted down in 1978, the front-page story said the defeat gave "the gay rights movement its greatest political victory in American history."

Less than three weeks later, Milk and Mayor George Moscone would be gunned down in City Hall by disgruntled ex-Supervisor Dan White.

Reporters from all over turned to the BAR, which had the best connections to write the most powerful stories from within the gay community about the impact of their fallen leader. Their stories of the candlelight vigils, and the "White Night" riots after White's 1979 voluntary-manslaughter conviction, were widely read by a mainstream audience.

By this time, the BAR was making money and able to hire trained journalists to go after larger issues, just in time for one of the largest to hit the gay community: AIDS.

The BAR was the first paper to acknowledge that so many men were dying. In 1983, it sent reporters to investigate the link between AIDS and the gay bathhouses.

Most significantly, the paper acknowledged AIDS on its obituary page. While many mainstream papers were using euphemisms such as pneumonia or "a long illness" as cause of death, the BAR wasn't shy.

Documenting toll of AIDS

As reporters watched the line to place an obituary grow outside their offices, they were inspired, in 1989, to run an eight-page section with the pictures and names of the more than 500 people who died of the virus that year. It was a political choice to give dignity to the people everyone else was trying not to talk about, Horn said.

"The response was overwhelming," Yamashita said. "People are still talking about it. That was the first time the BAR made the national press."

The deluge of obits wouldn't subside for nine more years, when the shock over a day without any obit requests prompted the staff to tear up the front page and replace it with a new one with a screamer headline: No Obits.

The paper examined the finances of gay charities, even taking beloved ones to task. After writing about the shoddy bookkeeping of Project Open Hand, which at the time delivered meals to homebound AIDS patients, the charity hired a board and began tracking its finances. The director took a pay cut.

The paper also criticized then-Mayor Dianne Feinstein for voting against allowing domestic partners to qualify for city health benefits. She has since changed her opinion, and the city, and eventually state, went on to recognize domestic partnerships.

The issues the BAR felt most strongly about were starting to work their way into the national dialogue.

"By the '90s, the Chronicle had a reporter covering LGBT issues," said BAR News Editor Cynthia Laird. "That to us, was a sign of progress. It was also like, 'Uh-oh. We're a weekly - it's hard to beat a daily.' "

Issues unique to community

But the BAR was able to hold its own with unique stories about the community, and even gay angles on mainstream stories. For example, the BAR knew, long before anyone else, that dog-mauling victim Diane Whipple was in a lesbian relationship when she was killed, Laird said.

Many of the BAR's pages these days are dedicated to marriage equality, from the day in early 2004 when then-Mayor Gavin Newsom began issuing marriage licenses to same-sex couples at City Hall, to the latest twists and turns of the effort to overturn Proposition 8, the ballot initiative that invalidated same-sex marriages in California.

The BAR was there, front and center, in June 2008 when lesbian pioneers Phyllis Lyon and Del Martin tied the knot on their 58-year relationship at City Hall.

These days, it feels as though the staff is filing more reports of victories - the repeal of "don't ask, don't tell," promising developments toward an AIDS vaccine, and increasing numbers of states allowing gay couples to marry. Whereas the BAR used to be the only place to find major coverage of the Gay Pride Parade, now it's reprinted, tweeted and blogged everywhere, to almost every major city in the world.

"We want to continue to be relevant," Horn said, "and report stories that are in depth and stay ahead of one of the largest civil rights stories of our times." {sbox}

Bay Area Reporter 40th Anniversary Retrospective: 9 a.m.-5 p.m. Mon.-Fri. Free; group tours available. Through June 30. Union Bank, 400 California St., S.F.