In the 1991-95 period, Tibet earned 958 million yuan (HK$891 million) from foreign tourists, making it one of the region's most important revenue earners, said Suolan Duojie, the head of its tourism bureau.

In 1996, Tibet earned 280 million yuan from 33,000 foreign tourists and aims to increase that number by 33 per cent by the year 2000.

The top three sources of visitors are the United States, Germany and Japan, with Europeans and Americans accounting for 65 to 70 per cent of the total.

They come to see the treasures of Tibetan Buddhism in monasteries built as long as 1,300 years ago and the monks who live in them and the pilgrims who come to pray.

They can enjoy trekking, mountain-climbing, nature reserves and religious festivals. The sky is a crystal-clear blue and the moody weather makes the landscape change by the hour.

The problem is that nearly all the foreign tourists come during the three months from July to September. The average annual occupancy rate of hotels for foreigners is just 25 to 30 per cent, with a rate of more than 90 per cent in the busy season and zero during the winter months.

To attract more off-peak visitors, the region aims to cut hotel, food and transport prices by 15 per cent between November and March but does not plan to allow foreigners to travel here on their own. Suolan Duojie said conditions were not ripe for that.

'We tried this from 1984 to 1986 and about eight tourists died because they went to remote, unpopulated areas and were killed by avalanches or froze to death,' he said.

'We found out about them months later when we had calls from the embassies in Beijing. Sometimes we could not find the bodies. So, for the safety of tourists, we have to guide them.' A second reason is that some tourists did things inappropriate for a visitor, such as supporting independence for Tibet and spreading splittist rumours, he said.

All foreign visitors to Tibet have to come on an organised tour, even if it is a tour of one person, accompanied by a guide. This preoccupation with security appears to be an obstacle for the tourism industry.

But the bureau's deputy director, Zhang Wansheng, insisted that the region's army and police does not oppose plans to increase the number of foreign visitors, quite the contrary.

So many years of reform and the open-door policy have proved that economic development leads to stability. The tourist industry brings wealth to the people, he said. Zhang and his colleagues have plenty of other things to worry about.

Tibet, which has an area of 1.2 million square kilometres, one-eighth of China's land mass, has a single civil airport, Gongar, 80 kilometres north of Lhasa, with connections to Beijing, Chengdu, Chongqing, Xian and Kathmandu.

In winter the flights to Xian and Kathmandu are suspended. Nearly all flights arrive and depart in the morning, because erratic weather makes flying uncertain from mid-afternoon.

The other points of entry are by road from Golmud, Chengdu, Xinjiang, Yunnan and Kathmandu - spectacular routes lasting several days on some of the highest highways in the world, but not for a traveller in a hurry.

Of the roads within Tibet, half are tarmaced and the rest are made of sand and stones. The tourist industry uses imported Japanese vehicles. Distances between tourist spots are far, exhausting the travellers.

An official report by the tourism bureau called for the opening of more routes to Lhasa airport and the development of air traffic within Tibet.

As she watched a performance of Tibetan dancing in Lhasa, Anne Born, a nurse from Zurich, said that the 10 people in her group each paid 1,520 yuan to hire a bus in Golmud, covering the cost of the entry permit, the bus and the first night in Lhasa.

'By hiring the bus, we were able to stop where we wanted along the way. The altitude was up to 4,000 metres. It takes 32 hours from Golmud,' she said.

But Lhasa is like any other Chinese city. Some people say that they do not want to give money to China.

This raises another obstacle in promoting Tibet as a tourist destination - its image, thanks to the work of the Dalai Lama and his government in exile which portrays the region as one under Chinese occupation.

Bob Chambers, a retired physics professor from Bristol, England, said that he and his wife were concerned about coming, about whether they should give money to the Chinese oppressor.

'Pictures of the Dalai Lama have been moved from the monasteries. Once I get home, I would say to people: think twice about coming.

'Have the Chinese improved the treatment of Tibetans? Lhasa gives the impression of a Chinese city, with only a small Tibetan part,' he said.

The oppression is not so obvious. People are free to worship and the numbers are more than in Ladakh (northern India), where there are many monasteries and few worshippers. Here it is the reverse. For Ralph Friedmann, a German teaching at the China-European International Business School in Shanghai, the main complaint was money.

'I paid 8,000 yuan for three days, including the travel permit, the flight from Chengdu to Lhasa and back, the hotel and tour guide,' he said.

'I paid the travel agent 200 yuan a day for the guide but she received only 50.

'The agent charged me 500 yuan for transport from the airport to Lhasa city but the taxi fare was only 150. The travel agencies cheat us.' Despite that, he said he would recommend a trip there to his friends, to see the old town in Lhasa and the warmth and life of Tibetan people.

Another problem is the altitude sickness experienced by some visitors because Tibet lies at 4,000 metres above sea level and has 70 per cent of the oxygen of inland China in summer, falling to 50 per cent in winter.

Han Chinese officials working in Tibet are given three months off every 18 months to enable them to go home and recover from the effect of the climate and its side-effects.