Aubenas, 44, a reporter for the daily Liberation, searched the crowd for familiar faces and shared kisses with friends.
"For me, all hypotheses remain open," she told a packed news conference, two days after her return to France.
With flashes of humour and surprising bravado, Aubenas recounted the drama she and her Iraqi guide, Hussein Hanun al-Saadi, endured for more than five months.
The reporter and her guide were kidnapped while conducting interviews at a refugee camp outside Baghdad.
Four armed men whisked them to a private home under the pretext that al-Saadi might have stolen some money, Aubenas said.
Then a young man told her: "Don't you know? You're kidnapped."
She and her guide were then separated. She was moved to a second house and ordered to put on a sweat suit with "Titanic" written on it.
Aubenas' captors renamed her, first calling her "Laila," then "No 6". They continually expressed frustration that her captivity was not paying off.
"You're a lousy hostage," she was told at one point.
The captors of Aubenas (C) told
her she was a lousy hostage
The only public sign that Aubenas was alive during the ordeal was a videotape recorded by her captors that emerged on 1 March. She looked pale and pleaded for help.
Her guards were gleeful at the reaction in France.
Aubenas said her guard, Hadji, described his group as "fighting mujahidin combating the Americans in Iraq" and said the group was part of a "religious movement".
Hungry or sick
"Every day I was either hungry or sick," she said.
"I thought they were going to make an example of us before the election by shooting us in the head on the internet," she said referring to the January parliamentary elections in Iraq.
But it was the waiting in a poorly illuminated, two- by four-metre cellar room under a private home that emerged as the most daunting aspect of her captivity.
"You're always waiting for things," she said, from sounds to visits from the captors. "You wait to go to the bathroom. It kills time.
"You wait permanently, but it's a frustrated wait ... . It was unimaginable that I was going to stay there for five months without being transferred somewhere else," she said.
Forbidden from talking, Aubenas estimates that she spoke 80 words a day and walked 24 steps daily - to and from the bathroom - during her captivity.
Hussein Hanun said his family
was always on his mind
So complete was her isolation that she said it took weeks before she learned that her cellmate - 90cm from her - was al-Saadi, her guide.
"I was held in the same place as Florence but I could not see her because we were blindfolded.
We didn't speak," al-Saadi said said after his emotional homecoming in Baghdad following his release.
"I didn't know how they were treating her because they spoke to her very softly," said al-Saadi, once an air force fighter pilot under the former government of Saddam Hussein.
Thin and finding it hard to concentrate, the 45-year-old spoke of how he missed his family and his euphoria at being freed.
Al-Saadi said he was properly treated.
He made no mention of the Romanians.
The father of four was reunited with his family on Sunday, a day after his release, in a chaotic celebration marked with joy, tears, sweets and a freshly slaughtered sheep.
"What hurt most was being separated from my wife and children," he said. "I am really happy to be back among those I love; my family never left my mind.
"I was thinking about my children and my wife all the time, especially since I could imagine her anguish and know how she suffers from high blood pressure.
"I was really anxious despite being treated properly by those I was with," he added.
"They told me, you will get out of here and get back with your family, we have nothing against you and we are good Muslims who respect human feelings"
"They regularly gave me news of my family and when I tried to know more, they said 'don't worry, we are taking care of them'."
They also insisted he was their guest.
"They told me, you will get out of here and get back with your family, we have nothing against you and we are good Muslims who respect human feelings," the former hostage said.
"When I began to pray, they were pleased and when I fasted, they asked me which dish I wanted to end the fast with," he said.
Of his captors he said: "They were Islamists."
Speaking of his liberation, al-Saadi said: "One morning, they came and told me 'you are going back to your loved ones' and I was mad with joy.
"They filmed us, saying 'you will see these images and hear your statements on television this evening surrounded by those dearest to you'.
"I could hardly believe it, and thank God the dream came true. That said, I still have not seen the images on television."
Back in France, Aubenas said she was called to go upstairs: "No 6, toilet." Then came the magic words: "Today, Paris."
She and her guide were served tea on Saturday, the day of release. A roast chicken was cooked and Aubenas was presented with a gift of rings and perfume. Their possessions were returned intact.
Aubenas said al-Saadi convinced her to give her captors the $80 in her purse. "It's the tradition," she said he told her.
One enigma surrounding the hostages' release only deepened at the news conference, when the French reporter refused to confirm the accounts of Romanian journalists who said they shared the basement cell with her during their captivity.
They were freed on 22 May. Former Romanian hostage Marie Jeanne Ion of Prima TV told her station on Tuesday that "things should stay the way they are". She also said: "It is clear that something happened there and we don't know what."