Suspects have started arriving in a courtroom ahead of their trial over the 2015 Paris attacks.
Twenty men are accused of being involved in the atrocities, with a heavy security presence in place outside.
Police secured the area near the Paris courthouse on the Ile de la Cite during the arrival of a convoy believed to be carrying the defendants.
The so-called Islamic State (IS) terrorist attacks, which took place on 13 November 2015, killed 130 people and injured hundreds more.
Nine gunmen and suicide bombers struck within minutes of each other at France’s national football stadium, the Bataclan concert hall, and restaurants and cafes in the city.
Lawyers, journalists, victims and families who lost loved ones have started to arrive at the court for the opening of the country’s biggest criminal trial in history.
The alleged lone survivor of the IS group, Salah Abdeslam, is expected to be the key defendant and is the only one charged with murder.
The same IS network went on to strike Brussels months later, killing another 32 people.
31-year-old Abdeslam, who abandoned his rental car in northern Paris and allegedly discarded a malfunctioning suicide vest before fleeing home to Brussels, has refused to speak to investigators.
He will be questioned several times throughout the trial, which is expected to last around nine months.
He is thought to hold the answers to key questions about the attacks and the people who planned them, both in Europe and abroad.
Six of the 20 men accused will be tried in absentia, with five believed to have likely died in Syria.
The modern courtroom was constructed within the 13th-century Palais de Justice in Paris, where Marie Antoinette and Emile Zola faced trial, among others.
Throughout September, the trial will focus on laying out police and forensic evidence before moving on to the testimonies from victims in October.
From November to December, officials including the former French president Francois Hollande will give evidence as will relatives of the attackers.
Speaking to reporters on Wednesday, Mr Hollande said: “I will answer any questions about my decisions during that terrible night. I will answer any questions if they are asked, about what our intelligence was.
“What is the goal of the terrorists? Of course, to try to harm our way of life, and fight the war because we are waging one against them, but what they want the most is to divide us. That is why I am proud of the French because they didn’t divide after November 13th.”
Dominique Kielemoes, whose son bled to death at one of the cafes that night, said the month dedicated to victims’ testimonies at the trial will be crucial to both their own healing and that of the nation.
“The assassins, these terrorists, thought they were firing into the crowd, into a mass of people. But it wasn’t a mass – these were individuals who had a life, who loved, had hopes and expectations, and that we need to talk about at the trial. It’s important,” she said.
For the first time, victims have been given the option to listen to the trial from home using a secure audio link with a 30-minute delay.
The proceeding will not be televised but will be recorded for archival purposes – which has only been used in a handful of cases in the country that are considered to be of historical value.