The international Olympic Committee is to hold a memorial in Rio for the 11 Israelis killed at the 1972 Games in Munich, after 44 years of campaigning by relatives of the victims.
Widow Ankie Spitzer, whose husband Andre - a fencing coach - was taken hostage and murdered by Palestinian militants from the Black September group, will be present at the unveiling of a memorial stone in the athletes' village.
She said: "Nobody ever thought something so terrible would happen."
"Just a few hours after the murder I went into the room of my husband where they were all held hostage.
"I cannot even describe to you the chaos when I opened the door of the apartment."
The terrorists, who had murdered two Israeli athletes, demanded the release of more than 200 Palestinian prisoners in Israeli jails.
When a rescue attempt by German police failed, the remaining hostages, and a policeman, were killed.
After four decades of campaigning, the 70-year-old said she had never given up on her wish to secure at the Olympics a moment's silence in honour of her late husband.
The widower came to London in 2012 to plead with former IOC president Jacques Rogge for a memorial at the London games, but was devastated after her appeal to him failed.
