At the foot of the 3km climb of the Route de la Combe d'Ire above Lake Annecy, a sign in French, German and English warns: "dangerous road".
Up that track on Wednesday afternoon, there drove a British-registered BMW carrying a British-Iraqi-Swedish family of five. Soon afterwards two cyclists started on the climb. Near the top, the second cyclist, a local French man, overtook the other, a Briton.
When the British cyclist reached the dirt car-park at the top of the track, he found a scene of unbelievable butchery. A girl of about seven or eight years old staggered towards him and then collapsed. She had head injuries, inflicted by a blunt instrument, and a bullet wound in her shoulder.
The cyclist who had overtaken him minutes before lay dead, shot in the head. The BMW was standing with its motor still running. The British cyclist, a former RAF officer who has a holiday home near by, placed the injured girl in the recovery position on her side. He telephoned the emergency services.
He smashed the driver's side window of the BMW to cut the ignition and discovered within what a senior French investigator called a "scene of immense savagery". A man and two women had been shot dead, two of them in the head.
He did not notice – and neither did French security forces for an unbelievable eight hours – that a girl of four was cowering, alive and unharmed, at the feet of her dead mother.
Last night, revulsion, mystery and official embarrassment swirled around the murders in one of the most popular tourist areas in France. Some French officials said the slaughter resembled a targeted, professional killing. Others said that the massacre of the family was too savage to be professional.
The car was owned by an Iraqi-born British citizen, Saad Al-Hilli, 50, who had been camping with his family near by since Monday. British officials are satisfied that Mr Al-Hilli was the man found in the driver's seat with his head smashed by a close-range shot from an automatic pistol.
The two women found dead in the back seat of the car are thought to have been his wife, Ikbal, and her mother. Swedish and Iraqi passports were found on the body of the older woman. French officials insist that her face and that of the male victim were too badly damaged to allow formal identification until DNA tests are performed on samples flown from Britain today.
The French authorities also struggled to explain how the four-year-old, believed to be Mr Al-Hilli's daughter Zeena, was found alive inside the car after so much time had elapsed – unharmed but paralysed with fear.
The little girl had taken refuge beneath the skirts of her dead mother and grandmother. Local gendarmes did not spot her and sealed off the car while a top-level, crime-scene investigation unit travelled by car and helicopter from Paris. She was discovered only after other campers told investigators that the missing family had two children.
The older girl, Zeitab, aged seven or eight, was saved by the prompt action of the British cyclist. She was in an artificially-induced coma at a hospital in Grenoble last night. Her life was said to be no longer in danger after a series of lengthy operations. The smaller girl was also in hospital under surveillance in the company of a senior British diplomat.
The murdered cyclist, named as Sylvain Mollier, 45, a local man who had three children, was also shot in the head at point-blank range. He is believed to have been silenced after stumbling on the killings.
Sources in the investigation told the local French media yesterday that the murders – near the village of Chevaline, 10 miles from Annecy – resembled an "assassination rather than a robbery which went wrong". No shots were heard, suggesting that a silencer may have been used.
The public prosecutor for the Annecy region, Eric Maillaud, was asked at a press conference yesterday whether he believed that he was dealing with "professional killers".
He replied: "To talk of a professional killing is conjecture. I would rather speak of savagery. But it is clear that whoever carried out this attack set out to kill."
He went on to say that the two small survivors were "under police protection" in case the killers attempted to silence "witnesses that they had believed, until now, not to exist".
Mr Maillaud faced hostile questioning, from both French and British journalists, on the failure of the 60 gendarmes on the scene to notice that there was small girl alive inside the car for eight hours. He said that it was crucial that the car should be "sealed off" to prevent the "pollution" of evidence which might help to catch the killers.
Heat-seeking equipment had been used to check for survivors but did not pick up the presence of the child curled up at her dead mother's feet below the back seat.
"She remained prostrate beneath the skirts of her loved ones in a jumble of bags for nearly eight hours. She did not move in all that time," Mr Maillaud said. She was found only after campers at the Solitaire du Lac campsite beside Lake Annecy told investigators that they had seen two children picking apples with their mother earlier that day.
Mr Maillaud said that he believed the little girl lay petrified in the car after the gendarmes arrived because she "didn't know the good guys from the bad guys".
"She began to smile and speak in English to the woman gendarme who took her in her arms after she was rescued from the car … She told us she heard screams and noises but she can't say much more."
Earlier, in a radio interview, Mr Maillaud said that the little girl had "asked for her mummy and soon realised that her mummy was no longer there".
Investigators found 15 cartridge cases scattered around the car and several bullet impacts on the windows but not on the body-work. The rounds are believed to have been fired from an automatic pistol or several automatic pistols.
Mr Maillaud said that he hoped the two little survivors would be able, eventually, to help the authorities to piece together what happened on the Route de la Combe d'Ire. "At the moment, we are confronted with a crime of immense savagery," he said. "As for why these people were killed at this place and at this time, there is, so far, no way to answer that."
Timeline: Death in the Alps
5 Sept, 3.48pm A British cyclist calls the French police after finding three people shot dead in a car and the body of a French cyclist, also shot dead, near Lake Annecy. The man first saw a young girl collapse and went to her aid before contacting the emergency services. He then approached the bullet-ridden BMW, finding a dead man in the driver's seat and two dead women in the back.
7.30pm The first reports emerge, quoting a French official who says five people are dead. The official confirms the seven-year-old girl was found alive.
9.25pm Annecy prosecutor Eric Maillaud says no weapon was found near the scene, which was like something seen "in a film".
6 Sept, 5am Officials confirm the victims were a British family. They also reveal a four-year-old girl was uninjured inside the BMW.
6am Mr Maillaud says the four-year-old was discovered "frozen still" under dead bodies during a forensic examination of the car, eight hours after the initial discovery. He says the gun used in the killings was believed to be a semi-automatic pistol. He adds "a very large number" of shots were fired and 15 bullet cartridges were found.
12.30pm It emerges that the seven-year-old girl was beaten on the head and had brain injuries. Mr Maillaud says the four-year-old was spotted late because police sealed off the area and waited for back-up from Paris. The dead cyclist is named locally as Sylvain Mollier.
1.50pm The dead man in the car is named by French media as Saad al-Hilli, from Claygate, near Esher in Surrey. Mr Al-Hilli, in his 50s, was the driver of the BMW.
2.50pm Three of the four victims, including Mr Al-Hilli, were shot in the middle of the head in an act of "gross savagery", Mr Maillaud says.
The prosecutor reveals that Mr Al-Hilli was originally from Iraq and held British citizenship. It emerges that Swedish and Iraqi passports had also been recovered, along with the driver's British passport.