At age 40, the custom-built menorah still looks good: a sleek steel frame, a polished mahogany surface, 22 feet tall and so heavy that it takes a crane to hoist it.

On Sunday, Dec. 6, crowds in Union Square will gather at the foot of this awe-inspiring structure as it’s lit for the first night of Hanukkah — a San Francisco tradition that began way back in 1975.

One year earlier, Chabad lit a giant menorah a few steps from the Liberty Bell in Philadelphia. Inspired by that first public lighting and then the world’s second in Union Square, Chabad chapters slowly but surely began holding similar ceremonies across the country and around the world. This year, Chabad-sponsored menorah-lightings will occur from Red Square in Moscow to the Eiffel Tower in Paris — in all, 678 cities in 38 countries, according to the organization’s website.

There was a time when concerns about the church-state divide prevented this sort of public event. The ACLU and even some Jewish organizations took Chabad to court, petitioning city councils to prevent the menorah lightings.

For the most part, San Francisco has welcomed the free event, despite opposition from segments of the Jewish community that lingered for years. However, most have come to see the ceremony as a cheery source of community togetherness for Jews and non-Jews alike.

Cheerleader-in-chief has been Rabbi Yosef Langer of Chabad of SF. He helped organize the first lighting 40 years ago and soon became the main point person, working with politicians, rock stars and Jewish community leaders to turn the annual lightings into a highly anticipated event attended by thousands.

Forty years on, he feels grateful the Union Square menorah lighting caught on.

“The mitzvah of the menorah is to glorify miracles,” Langer says. “The more you can bring the light to the Jewish people and beyond, the more you bring religious freedom to everyone. Light pushes away the darkness.”

In addition to the menorah lighting, the Harley-riding rabbi has a summertime gig as the “Rally Rabbi,” blowing the shofar at AT&T Park when the Giants play on Jewish Heritage Night. He is the only Orthodox rabbi with his own bobblehead.

The Union Square menorah lighting ceremony — held on each of Hanukkah’s eight nights — is among his proudest achievements, though he admits he doesn’t do it alone and never has. For example, George Zimmer, founder of Men’s Wearhouse, is a big booster and financial supporter.

Another key player was Bill Graham, the German-born Holocaust refugee turned rock legend. He helped finance and promote the lighting from 1975 until his death at age 60 in a 1991 helicopter crash. Two years after that, San Francisco Mayor Frank Jordan declared that the first Sunday of Hanukkah always would be designated Bill Graham Menorah Day.

That day has become both a holiday and a party. While the nightly lightings draw decent crowds — and there’s always a big crowd for the first night — Bill Graham Menorah Day is a huge draw, with families enjoying musical performances, Hanukkah craft projects and special guests. Many attendees clutch small candles, and as the rabbi walks through the crowd, torch in hand, he lights them. As the sky darkens, the glow of a thousand candles illuminates Union Square.

Then, as the rabbi and other dignitaries ascend the scaffold behind the menorah, the blessings are said en masse and the Hanukkah candles (actual candles underneath glass) are lit.

This year, Bill Graham Menorah Day happens to fall on the first night of Hanukkah, so an extra special buzz is anticipated for the Sunday, Dec. 6, event which will begin at 4:30 p.m.

The Bill Graham Menorah Project, a program of Chabad of SF, manages the event, an undertaking that includes promotion and fundraising (it costs around $40,000 every year). The website www.billgrahammenorah.org includes photos and videos and this year’s schedule, among other things.

“Bill supported it and was proud of [the menorah lighting],” says Billy Cohen, who co-chairs the Menorah Project. “But he also had a low-key kind of approach to it. It was one part of his life where he really didn’t put himself center-stage. He was in the crowd, and didn’t participate in the lighting. He was very modest in relation to it.”

Graham’s influence brought a touch of rock ’n’ roll to the event. Over the years, in addition to participation by politicians such as Mayor Ed Lee and state Senator Mark Leno, celebrity candle lighters have appeared, including songwriter Sammy Cahn and musicians Carlos Santana, Matisyahu, Country Joe McDonald, Peter Albin (Big Brother and the Holding Company) and Perry Farrell (Jane’s Addiction).

Langer and Graham were close, though not even the rabbi could avoid Graham’s infamous temper. Langer recalls a time when Graham agreed to attend Shabbat dinner at Chabad, and to promote the dinner, Langer used imagery of rock bands Graham was not fond of.

Graham called Langer and read him the riot act.

“He said ‘I’m going to come this time, but I never want to hear from you again,’ and he slammed down the phone,” Langer recalls. “So he shows up [at the dinner], comes up to me and I said, ‘Bill, I’m so sorry. I made a mistake.’ He said, ‘Yosef, it’s OK. Don’t worry about a thing.’ He stayed until 2:30 in the morning, talking about God and rock and roll.”

One of Langer’s other favorite Bill Graham stories took place  when Graham showed up late one year and missed the actual lighting. Langer, still 20 feet up, noticed Graham standing adjacent to the Christmas tree, another Union Square staple and, as it happened, partially sponsored by Graham that year.

Langer called out to Graham, complimenting him on the dazzlingly decorated tree.

“He looks up to the menorah 20 feet high,” Langer recalls. “He pauses and he says one word: ‘Survival,’ then turns around and walks out of the square. It showed me why this kid who crossed [Nazi-occupied] Europe came to the menorah every year.”

In 1972, at the behest of Rabbi Shlomo Cunin of Chabad in Los Angeles, Rabbi Chaim Drizin moved into an old fraternity house on Piedmont Avenue in Berkeley. It became the world’s second Chabad house after Cunin opened the first in Los Angeles in 1969. (Today, there are more than 3,000 Chabad chapters worldwide.)

In 1975, Drizin welcomed to his staff the newly ordained Rabbi Yosef Langer and his wife, Hinda, who had been living in Los Angeles. They soon put their heads together with Drizin and Zev Putterman, who for a time produced television programs for KQED and KGO, to find ways to celebrate Jewish life in a more public manner.

They decided on an outdoor menorah lighting ceremony in the most public place possible. In the Bay Area, that meant San Francisco’s Union Square.

With the proudly Jewish but notoriously secular Graham helping with funding, the steel-and-mahogany menorah was constructed. The Union Square space was rented from the Recreation and Park Department, and on Nov. 29, 1975, Langer was hoisted in a cherry picker to light the first candle.

More than 1,000 people were there to see it.

“I helped produce the event,” Langer remembers, “and lit the torch, which is to this day my favorite part of the experience.”

“It was very dramatic to come into Union Square and see this huge menorah there,” Hinda Langer recalls. “I just thought, ‘Wow, this is fascinating.’ But it’s only in retrospect that you see history in the making. It took a few years before this caught on.”

It also had to withstand a bit of controversy. Much as lawsuits against crèches in public spaces made headlines in the 1970s and 1980s, so, too, did public menorah lighting trouble some people, including Jews. Langer remembers a Jewish Community Relations Council survey in the mid-to-late-’80s that found half of Bay Area Jews opposed to a public Hanukkah celebration.

Through the first decade of the Union Square menorah’s existence, the S.F.-based JCRC officially opposed all religious symbols — including menorahs — in or on government buildings and structures, or any such display if it were publicly financed. However, in 1985, the JCRC concluded that privately funded, temporarily erected religious symbols in forums that are traditional free speech zones, such as Union Square, were permissible.

“Overnight, opposition to the menorah dissipated in the community,” says Rabbi Doug Kahn, JCRC’s executive director.  “I use this as an example of the power of consensus at its best, a policy with real teeth and nuance. Everybody could live with this agreement.”

Hinda Langer says the public lighting fits with Jewish law. She cites the talmudic prescription of pirsumei nisah, or “publicizing the miracle,” which requires Jews to go public with Hanukkah. It’s why families put their menorahs in the window for all to see.

“It’s an educational tool for others about Judaism,” she says. “It’s an aha moment for people in the crowd, seeing this beautiful candelabra lit in public. [The menorah lighting] fulfills the purpose of a public, positive Jewish identity event.”

The event has faced other difficulties besides church-state divisions. Sometimes the weather refuses to cooperate, and once the lighting was rained out.

Frequent attendee Ken Margolis of San Bruno says showers have never stopped him.

“Rain happens,” says Margolis, who works with the nonprofit Save the Earth Foundation. “The craziest thing about these menorah lightings is that there can be a crowd of people in a torrential downpour. Rain doesn’t hold people back.”

Langer one other year drove into San Francisco for the lighting even though a storm pounded the city. Looking from afar, he saw a break in the downpour exactly in the downtown area. The lighting went on as planned with nary a drop.

Even when it does rain, Langer says the sight of a sea of umbrellas makes him happy because it shows a “determination to be connected to the light.”

Billy Cohen worked for Graham, having befriended Graham’s son, David, in college. In addition to attending the lightings, Cohen remembers an epic meal at the Graham house when he dined with Jerry Garcia and Bob Weir of the Grateful Dead.

“Bill had been this amazing figure in my life,” Cohen says. “A true mentor. For me personally, his death was very tough. I met [Langer] at some of the memorials for Bill, and I felt very at home, very energized. It was a lovely thing.”

Cohen grew up in a Reform household in New York, but says he found a deeper connection to Judaism through Langer and Chabad of San Francisco. He loves working on the menorah project because, as he puts it, “we pull people in.”

“It really shows the idea of why you put the menorah in the window and shine the light onto the street,” Cohen says. “It is a brilliant proof of concept. We’re in San Francisco, so there are people from all over the world. It’s a genuine cultural exchange, a bridge-building event and an embrace of the community at-large.”

The Langers have up their sleeves what they hope will be their next miracle: a new Chabad center, to be opened south of Market Street at Natoma and Sixth streets, that will serve as a shul, community center, Torah study hall and hangout in what has long been a blighted San Francisco neighborhood.

Bob Dylan fans will get a kick out of the name of the new center: Positively Sixth Street (“Positively 4th Street” was a Dylan hit in the mid-’60s). Langer signed a 15-year lease on the five-story, 4,000-square-foot building. The remodeling is nearly done, and Langer hopes to open the place before the end of the year.

“We’re trying to restore the richness of downtown San Francisco,” he says. “Market Street is being transformed by food, cafés, the arts. We want to be part of that, and we’re getting community support.”

However, before then Langer has some big Hanukkah candles to light, as the menorah is his “keystone project.”

“Our goal,” Hinda says, “is that every Jewish person knows that it’s Hanukkah. And for the rest of the world, we want them to know we Jews are involved with miracles, that we survived throughout history.”

For Margolis, a Chicago native who moved to California in the early 1980s, the menorah lighting was the catalyst for a reintroduction to his Jewish roots.

“I thought it was a perfect connection to my heritage,” Margolis says. “Chabad does reach people like me, and connects them to their heritage. The reason I help Chabad when I can is because the Torah is really important.”

For Langer, who usually dances his way through the Union Square crowd on Hanukkah, it’s all about giving back.

“A Hassid is like a lamplighter,” he says. “The Chabad masters took this idea established by the Baal Shem Tov [founder of Hassidism] to go to the marketplace. That’s where the congregations of the world are today.”