France is bracing for one of its biggest-ever criminal trials, with 66 men and women set to face charges of rape and child sex abuse this week.
The courtroom in Angers: A verdict is expected in June
The trial will get under way on Thursday in a specially built hall in Angers, western France.
More than 60 lawyers will take part and the prosecution case runs to 430 pages, the French news agency AFP reports.
There are 45 alleged child victims - the oldest aged 14 and the youngest just six months.
Of the 66 defendants, 39 face charges of raping children under 15 and of pimping. A total of 39 men and 27 women are going on trial.
The crimes could incur jail terms ranging up to 30 years.
The crimes allegedly took place between June 1999 and February 2002 in Angers' Saint-Leonard district.
The prosecution says most were perpetrated in the flat of a former convicted sex offender, and in sheds on garden allotments.
The crimes reportedly came to light when investigators monitored the activities of a convicted sex offender released in 1999. The two men allegedly ran the paedophile ring.
Nearly all the defendants were living on welfare benefits.
"Parents of one kid sold her for a new car tyre," said lawyer Philippe Cosnard, quoted by the AFP news agency. Other children were allegedly bartered for small sums of money, food or cigarettes.
A girl of 10 was allegedly raped by more than 30 adults.
Prosecutors say more than half of the accused have admitted their guilt.
But the prosecution hopes to avoid any repetition of the errors that plagued a previous high-profile paedophile trial - the Outreau case in northern France last year.
In that case, the accused spent months in prison awaiting trial and 13 people were implicated on the testimony of a woman who later admitted she had been lying.