Sixty-six defendants, some facing up to life imprisonment, were brought into a blue-carpeted courtroom specially built in this western city to hold them all.
Many of the 39 men and 27 women shifted uncomfortably in their seats, shoulders hunched, looking down at their shoes. Most replied timidly when asked, one by one, to stand, give their age, profession and address.
In French trials, defendants do not plead guilty or innocent at the start of proceedings. Court officials said about half of the accused had admitted involvement in the alleged crimes during questioning.
Investigators say 45 children — from 6 months to 14 years old — were raped or sexually abused from 1999 to 2002 by their parents or people close to them who paid money, food, cigarettes or liquor. A grandfather of some of the children allegedly filmed rapes and other abuse.
"To my knowledge, we've never seen a criminal case of this magnitude in France," said Pascal Rouiller, a lawyer for five suspects.
As the trial opened, the court ruled the hearings will be closed to the public to protect the victims' identities. Journalists will be allowed in, but under French law cannot use the names of the children or their parents.
The victims, who are in the care of social services, will not appear in court. Their testimony has been videotaped.
Psychological counseling is being offered to the jurors and the six judges to help them cope with the sordid testimony expected from a trial scheduled to last four months.
The defendants, aged from 27 to 73, mostly are from low-income households in the Saint-Leonard neighborhood of Angers, a town of 156,000 people some 165 miles southwest of Paris. Some were abused themselves as children. More than half are unemployed.
Defense lawyers plan to argue that government social workers, who dealt with many of the suspects, turned a blind eye to signs of abuse.
The case came to light in 2000, when a 16-year-old girl alleged she had been raped by her mother's boyfriend and his brother.
Three couples at the heart of the case lured their children and those of their friends, relatives and neighbors by saying they were going to "play doctor," the prosecution's 420-page legal filing charges. One girl was allegedly raped 45 times.
Three defendants face life imprisonment if convicted of raping minors under age 15 and of active participation in a prostitution ring. Thirty-six face up to 20 years imprisonment if convicted on similar charges.
Five defendants could be sentenced to 10 years in prison if found guilty of incestuous sexual abuse on children and 14 could face seven years if convicted of corrupting minors. The remaining eight are charge with failing to report the crimes and could be jailed for three years if convicted.
Some people who are thought to have worn masks while they raped children are feared to be at large. "The children speak of one tattooed woman who is not in the defendants' dock," Rouiller said.
The shadow of another pedophilia trial in the northern town of Outreau last year hangs over the case. That trial exposed shortcomings in the justice system because some defendants were wrongly accused. Although 10 were convicted, seven were acquitted after spending nearly three years in prison awaiting trial. The government agreed to pay each $130,000 compensation.
A follow-up inquiry recommended that investigators get better training in gathering testimony from children and that professionals be on hand when minors are questioned.
Experts said the short time-lag between the Outreau and Angers trials was coincidental and not a sign that pedophilia is surging in France. Government figures do not show sharp increases in convictions for child rape or abuse.
But experts say investigators, courts, child professionals and news media are getting better at exposing a problem that has long existed.
"We can't know if there is more pedophilia and incest in France than before. We don't think so. However, we do think there are more revelations," said Thierry Choubrac, a child psychologist.
"We think that affairs like Angers must have existed before. They were just kept hidden, as family secrets," he added.
By Verena Von Derschau