By Candace Piette
BBC News, Aconcagua, Argentina
Jolting along a mountain path in a park-keeper's jeep in Argentina's Mendoza State, we are surrounded by a series of beautiful, dry sand-coloured mountain ranges.
Pinks and violets, greens and blues emerge from the shadows in the landscape around us.
We've come to see the highest mountain in the Americas, Aconcagua, in the park of the same name, which lies just ahead up the valley in full sunlight, its summit wreathed in snow.
The mountain, in the Andean range not far from the Chilean border, hit the headlines back in January.
A huge rescue attempt involving hundreds of local volunteers ended in tragedy. They tried to save a group of Italians in trouble near the summit - but a climber and her guide died.
Video footage of the guide's dying moments, shown on TV, shocked the public and raised questions about the ability of the Aconcagua Park to cope with emergencies.
Suddenly the radio crackles to life. The chief park-keeper, Daniel Cucciara, explains that he has just heard that a Russian climber, high above us, is in trouble.
Visitor numbers to Aconcagua have been increasing dramatically over the last decade, because of the fashion for dangerous sports.
More than 8,000 permits were issued in the 2008 climbing season. Out of these, half were for people aiming for the summit.
Most visitors to the park are from the United States or Europe. "Forty percent of the tourists who come here do no preparation at all," says Daniel Cucciara. "This causes serious problems for rescue teams when they get into trouble."
Aconcagua can be dangerous. The mountain is 6,962 metres high (22,840ft). Climbers tackle it without oxygen, and at its summit the air is 40% what it is at sea level.
The ''White Wind'' of Aconcagua - the clouds which descend quickly at the highest altitudes - can also catch climbers out. This year alone, 280 people had to be evacuated when they got into trouble. Many die, often from pulmonary embolisms or in accidents.
"If you come to Aconcagua you need to have a mountain culture," says Daniel Cucciara. "You need to have climbed other mountains. Here we are talking about one of the toughest mountains in the world to climb.
"You need to have trained for two or three years in gymnasiums, done a lot of running, and even then this doesn't mean you are going to make the summit. You never know how your body will respond to such high altitudes."
Alejandro Randis believes climbers are given a false sense of security
The mountain can beat even the most seasoned of climbers. Marcelo Hector Acosta co-ordinates the Mountain Guides school in Mendoza. He has climbed Aconcagua an amazing 35 times and took part in the rescue of the Italians and the guide, Federico Campanini, in January.
"It was all very strange. When we got there, we found a group of four climbers and Federico. He was in a bad way but he said 'save my people'. Under the system of triage, in an emergency, the victim in the worst condition has to be left, and that is what we had to do."
The video showed Federico stumbling and falling, unable to get up, in the final stages of a suspected pulmonary embolism.
The mountaineering community and the public in Argentina began asking questions about the park's ability to mount rescues at high altitude. There were calls for better rescue and shelter facilities at the higher base camps on Aconcagua.
Standing in front of the park's rescue helicopter, Guillermo Carmon, the Mendoza State secretary of the environment, says the park authorities are doing their best, although he admits the cost of rescues like the one in January is very high.
"This is one of the few places in the world where no-one is charged for a rescue, and we are very proud of that," he said.
"But we are now considering insisting climbers take out insurance to help us recover our search and rescue costs. Of the 280 rescues we operated this year, a third were risky and complicated."
For the mountain guide community in Mendoza who volunteer in park rescues, this cannot come soon enough. Veteran mountaineer Alejandro Randis believes the park is exaggerating its rescue capacity, giving climbers a false sense of security.
He believes that it is vital that climbers are told, clearly, about the risks.
"The park should spend more time and resources on telling climbers that what they are about to do is very dangerous, that it takes a long time and that on many days you can not rescue anybody because of the weather, which often makes it impossible to move," he said.
"Then it is up to each climber to take responsibility for their actions."
Mr Randis also argues that up until now, the park has been unrealistic about its capacity to finance rescues in terrain where helicopters cannot fly, and hundreds of people are needed to carry equipment and supplies quickly to high altitudes.
Those who die on the Aconcagua are buried in the shadow of the mountain
"Providing an adequate search and rescue operation is expensive, and the park does not have the money for that. It is a farce to say they are providing security for climbers."
In the shadow of Aconcagua, lies a small cemetery where climbers who died on the mountain are laid to rest. Pairs of climbing boots, hats and gloves have been left on tombstones by those who made the journey to the summit and returned.
But without better rescue services, it is likely that Aconcagua, the highest mountain in Latin America, will continue to claim lives.