By Andrew Keh – The New York Times.

MUNICH — The gray space is carved directly into a grassy hillside, evoking an open wound.

In this way, the Munich 1972 Massacre Memorial, set to open on Sept. 6, is emblematic of the pain that has endured for many since that year’s Olympic Games, when 11 members of the Israeli team and one German police officer were killed by members of the Palestinian group Black September.

The memorial, family members of the victims said, will bring them yet another step closer to peace.

“There are no happier people, no more satisfied people, than us,” said Ankie Spitzer, whose husband, Andre, a fencing coach, was among those killed at the Munich Games. “It took 45 years, but like I tell my kids, if you have a dream, pursue it, if you feel that it is just.”

Satisfaction has been a long time coming. The healing process? That still feels incomplete.

Family members of the victims — organized by Spitzer and Ilana Romano, the widow of the weight lifter Yossef Romano — spent decades asking the International Olympic Committee for a formal acknowledgment of the massacre at the Games. Last year, at the Summer Olympics in Rio de Janeiro, one finally took place, with a ceremony and the installation of a monument in the Olympic Village.

But Spitzer and the other families had also urged the Bavarian government for years to erect a comprehensive memorial and museum at the Olympic Park, where the Israeli team members were initially taken hostage. Two team members were killed there, and the rest, as well as the German policeman, died during a chaotic rescue attempt at a nearby air base.

Until now, a sculpture and plaque have been the two primary memorials in the Olympic Park. But for decades the memorial request was largely ignored, until more-sympathetic ears arrived in the leadership of the Olympic committee and the local government in recent years.

“It is late,” said Ludwig Spaenle, the Bavarian minister of culture, whose office led the project. “But it is not too late.”

The new memorial rests unassumingly along a quiet walking path in Munich’s Olympic Park. Visitors to the site descend a short set of steps to enter the main space, which has the effect of stepping into a sanctuary. The exhibition area, which measures about 1,700 square feet, seems almost like a cave, resting under a thick mound of grass and blending into a backdrop of linden trees.

Along the back wall, a large LED screen, about 36 feet long, will play a 27-minute loop of news footage broadcast during the crisis. In the center of the memorial, a triangular column will display biographical profiles of each victim in German and English, with photographs.

“Our design idea was to cut into the hill, to take something away from the landscape,” said Stephan Graebner, an architect at Brückner & Brückner, the German firm selected in 2014 to design the memorial. “When you think about the massacre, it took something away, cutting into the lives of the victims, the families, the Olympic Games. We wanted to fill this void with memory.”

Among the most poignant elements of the exhibition are the personal effects, one for each victim, that were photographed for the memorial.

There is, for example, a postcard that the athlete Ze’ev Friedman sent to his parents from Munich before the attack. It arrived in their mailbox days after his death. There is a copy of a telegram that Golda Meir, the former Israeli prime minister, sent to the United States to the parents of David Berger, an Israeli weight lifter who grew up in Shaker Heights, Ohio. “I know that no mortal word can assuage your grief,” Meir wrote to the Bergers, adding that “the pain is not only yours but that of a whole nation.”

Werner Karg, an official in the Bavarian ministry of culture, said it was unfortunate that haunting images of masked terrorists were more prominent in the public consciousness today than the memories, and the faces, of the victims. The memorial, he said, could help change that.

“We can show that these were individuals, ordinary people, not just names,” Karg said.

Spitzer has attended every Olympics since the Munich Games to press for a more concrete remembrance of the massacre. She was rebuffed for decades, she said, often being told that politics do not belong at the Olympics. That stance, the families knew, was always a convenient way to avoid the issue.

“We always said that if it had been the American Dream Team, we don’t think they would have to fight for such a long time and beg and ask,” Spitzer said.

At the 2012 Olympics in London, the International Olympic Committee shut down widespread calls for a televised moment of silence during the opening ceremony to mark the 40th anniversary of the massacre, a decision that drew criticism from many quarters and improvised moments from others. On NBC’s broadcast of that ceremony, for instance, the announcer Bob Costas paused his commentary for 12 seconds when the delegation from Israel entered the stadium, effectively creating his own moment of silence.

“Terrorist attacks and other outrages happen, sadly, on a constant basis,” Costas said in an interview. “But this one struck the Olympics itself. That’s what separated it: not that it was more tragic or more significant than others, but that it was directly tied to the Olympics.”

Progress started to come shortly thereafter. Spaenle, the Bavarian culture minister, met Spitzer and other victims’ families in 2012, months after the London Games, at a ceremony at Fürstenfeldbruck Air Base, where the hostage situation came to its tragic end. At that meeting, he pledged to work on the memorial project, and he met again with Spitzer and Romano several times in Germany and Israel.

Thomas Bach, who was elected president of the Olympic committee in 2013, proved more supportive of the families’ cause than his predecessors, and quickly backed the project, too. Bach, who won a gold medal in fencing for West Germany at the 1976 Games, also greenlighted the ceremony in the Olympic Village in Rio, where he read the names of the Munich victims.

“The murdered Israeli Olympians were victims of an attack at the heart of the Olympic Games and against all the Olympic values,” Bach said. “It is therefore fitting that these innocent victims should be remembered forever with a dignified memorial at a place close to the Olympic Village. It will be a symbol of remembrance and our shared grief.”

The memorial and exhibition cost about 2.4 million euros (more than $2.8 million), according to Karg, with contributions from the Bavarian government, the German federal government, the Olympic committee and the Foundation for Global Sports Development, an American organization focused on promoting sportsmanship.

The project will finish a year behind schedule. Pushback from local residents twice forced organizers to move the project site, making the architects redesign the memorial each time. The site will be open to the public after a closed ceremony on Sept. 6 attended by members of the German and Israeli governments, the Olympic committee and the victims’ families.

Barbara Holzer, an architect from Zurich who served on the jury to select the project proposal, said any memorial had to be “a site that gives room to societal and individual reflection.” That process, for many, will begin anew here.

Spaenle was an 11-year-old living near the Olympic Park when the massacre took place 45 years ago. He still remembers hearing the helicopters flying overhead when the terrorists were transferring the hostages to Fürstenfeldbruck, and he was inside the Olympic Stadium when Avery Brundage, the Olympic committee president at the time, controversially declared after their deaths that “the Games must go on.”

Spaenle has long been familiar with the two more–modest memorials at two other sites in the Olympic Park — a sculpture by the German artist Fritz Koenig and a plaque outside the apartment where the hostages were held — “but all the time, I felt like something was missing,” Spaenle said.

“This,” he said, “is the missing link.”