Belgium on Tuesday opened a memorial garden on the site where notorious serial killer Marc Dutroux imprisoned his young victims, more than a quarter of a century after his crimes shocked Europe.
Authorities in the city of Charleroi last year tore down the "house of horrors", in which Dutroux tortured and raped children in a soundproofed dungeon.
The fathers of two eight-year-old victims, Julie Lejeune and Melissa Russo, were there to formally inaugurate the tree-filled garden decorated with a mural of a child watching a kite soar into the sky.
"Thank you for preserving the memory of our little ones with this superb work," said Julie's father, Jean-Denis Lejeune, after a minute's silence.
He said it was important to remember that paedophilia "existed and that it still exists".
Sentenced in 2004 to life imprisonment, Dutroux, today aged 66, was found guilty on charges including kidnapping and raping six girls and young women from 1995-1996, and the murder of two of the teenagers.
The modest red-brick building in the Marcinelle suburb of Charleroi became infamous when in August 1996 Dutroux led police to two kidnapped girls, aged 14 and 12, cowering in the basement.
The investigation into Belgium's worst paedophile crimes established that Julie and Melissa had also been held at the property for months.
Their bodies were found buried at another property. A postmortem showed they had been starved to death.
- 'Marked for eternity' -
Public shock turned to fury as it emerged not only that police had missed a string of clues, but that Dutroux had been released from jail in 1992 after serving just three years of a 13-year sentence for the abduction and rape of five girls.
"There isn't anyone in Belgium who hasn't heard of these disappearances," said Charleroi mayor Paul Magnette.
"It was a tragedy of sufficiently universal scope that it must be marked for eternity."
Gino Russo, the father of victim Melissa, thanked the city for agreeing to his "express demand" that the underground dungeon be preserved beneath the monument.
Russo believes that important questions in the case remain unanswered and asked the basement be left intact for potential future investigations.
He told AFP it was "impossible" Melissa and Julie could have survived in the cramped cellar of just a few square metres for over 100 days without outside care.
"My indignation remains undiminished, it has not been appeased," he said.
Dutroux dropped a bid for parole in 2020 after a psychiatric report concluded he remained dangerous.
His former wife Michelle Martin, who was found guilty of aiding him, and a co-conspirator have already been released from jail.
Authorities also demolished another house this year in the village of Sars-la-Buissiere, where the bodies of Julie and Melissa were discovered.