THE enormous philosophy hall at Labrang Monastery was lit only by the rows of flickering yak butter lamps placed around the walls but through the gloom I could see hundreds of red-robed monks sitting in rows chanting Buddhist prayers.
As my eyes gradually became accustomed to the dim light I was able to see they were sitting on padded benches, the ceilings were draped with massive hangings and the walls were covered with religious paintings.
The monks sat cross-legged, wrapped in their robes, mostly with eyes shut, moving only to take the occasional drink of tea from bowls at their feet, concentrating so deeply on the words of the prayers that but for the movement of their lips they might have been asleep.
Mostly they chanted in unison, their voices echoing melodically around the huge empty space. But at times the the deep growly voice of some senior lama would take over, then the mass chanting would resume. And now and then drums or cymbals would briefly boom out, then lapse into silence.
As we watched, a team of novice monks carrying large jugs swept through the hall, topping up the tea bowls, all without a break in the praying.
"We have 1000 monks praying in here today," said the young monk who was showing us around. "Before the Cultural Revolution there would have been 3000."
Labrang, which is in one of China's autonomous Tibetan regions, suffered severely at the hands of the Red Guards with monks killed or injured, halls smashed up or burned down and the monastery forced to close for several years.
But it is now back in action again, once more a fully functioning monastery, though the number of monks is restricted to around 2000.
Founded in 1709, it is part of the yellow-hat sect of Buddhism, to which the Dalai Lama belongs, and he often visited here before he fled China following the Tibetan uprising in 1959.
It is an enormous place, bigger in size than the neighbouring town of Xiahe, with accommodation for thousands of monks or pilgrims, countless temples, libraries and study centres, plus the kitchens, hospitals, shops and schools needed to support a large community.
Twice a day there are guided tours of the monastery so at the appointed hour I joined those assembled in one of the large courtyards to await our guide.
As well as a constant stream of monks and pilgrims, from time to time donkeys, cows and yaks strolled across the courtyard, clearly on their way somewhere important.
Through an open doorway someone spied a large silver dish, like a satellite dish, being used to focus the sun's rays to heat a kettle.
From another doorway at the head of the courtyard music was coming so a couple of us strolled up to have a look. We stuck our heads cautiously inside to see if it was okay to look and a monk smiled a welcome.
In one corner of a small courtyard a dozen monks were playing symbols in a highly ritualised way, involving much synchronised waving of the bronze discs, as much a dance as a musical performance. We indicated our cameras and the monk by the door indicated we could take photos.
In another corner was a cluster of monks who were taking it in turns to perforance incredibly complicated dances. But when my companion started to photograph them the doorkeeper shouted "No" and indicated that it was time for us to move on.
By now our guide had arrived and in remarkably good English - which he explained he had studied for three years before enrolling at the monastery - he said it was acceptable to take any photos we liked outside, but not of monks and not inside the temples.
First he took us to one of the monastery's original temples - presumably making it 300 years old - which had been protected from the attacks by the Red Guards and so its 500 handwritten sutras, religious paintings and 32m-high statue of Buddha survived.
Around the edge of the temple several monks were seated, alternately chanting prayers and slurping enthusiastically from bowls.
"They have been praying from 6 o'clock to 10 o'clock this morning,"explained our guide, "and this is their lunch. It is their only meal of the day." - I guess that explained why they were eating so eagerly - "They will have bread, yoghurt, yak milk, butter and barley. Sometimes in the winter they will have meat because they need it to survive the cold."
The altars of all the temples we visited were lit with yak butter candles and in this one an elderly monk was carefully pouring off the melted butter around the wick and collecting it in a bowl.
For once I had trouble understanding our guide's explanation but I think what he said was that the yak butter was brought to the monastery by nomads from the surrounding mountains and sanctified by being burned in temple candles. Over winter the collected butter was used to make religious sculptures and come summer it was melted down again and given back to the nomads.
Our tour included a visit to the building where the yak butter sculptures were stored and we were even allowed to take photos of one group. Naturally enough they were all on religious themes, carved with incredible skill and brightly painted.
We also got to see the monastery museum which seemed to consist of gifts presented by visitors or memorabilia from notable monks.
I was interested to see in pride of place here a photo of the young boy chosen by the Chinese authorities as the Panchen Lama (the original choice made by the Dalai Lama has disappeared) making him the second-ranked lama in the Tibetan Buddhist hierarchy.
Were there, I asked, any photos of the Dalai Lama? "Yes," said the monk, "we have some." Then he changed the subject. But I'm pretty sure that a photo of a bespectacled lama in a corner of the museum showed the Dalai Lama as a young man.
And did they have any reincarnated lamas - living buddhas - at the monastery? "Oh, yes," said the monk with a smile, "we have more than a hundred."
Many of them would, he added after a pause, be among those praying at our final stop, the philosophy hall. "But you must not stop and look at the monks because that would be disrespectful."
As we explored Labrang our guide had explained that the philosophy school was the most important at the monastery and possibly the most influential in the Tibetan Buddhist world.
"There are 1000 monks studying at present. Only the best 20 students in the examinations are chosen to study here. I hope to work hard enough to be chosen next year."
Afterwards, as I wandered back through the open parts of the monastery and the adjacent main street of Xiahe it was difficult to relate the prayerful, studious side seen in the tour, with the very worldly attitude of the monks outside.
Most seemed to have mobile phones - when one in our group asked about this our guide explained that they needed such things to do their work efficiently - a few carried transistor radios blaring out pop tunes, they seemed to take taxis for even the shortest journey and were obviously avid shoppers.
Ordinary Tibetans, and the other races living in these rugged mountains, have supported great monasteries like Labrang for centuries. But, as the Chinese grip tightens and the modern world increasingly intrudes even in these remote areas you can't help wondering how much longer that can continue.
Jim Eagles visited China with help from Singapore airlines and World Expeditions.
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