During my first visit to Spiti, I had walked along the snow-covered track between Dhankar and Kibber. There are no hotels in all of Spiti and accommodation can be found only at the government rest houses. I had stayed at the homes of villagers whose warmth and hospitality never ceases to amaze me. They were mostly farmers who worked hard during the brief summer months to raise their crops of barley and peas. Sitting around the family hearth – a wood-burning stove in the middle of the kitchen – and sharing a simple meal with them, one felt the outside world to be unimaginably remote.

Returning to Spiti now, after many years, I saw a greatly expanded Kaza. I was dreading and preparing my self for the worst but was relieved to find, despite the inevitable signs of progress, that the old town still retained some of its medieval charm, with its traditional mud houses and narrow alleys. The bazaar was packed with shops and stalls and there were even the ubiquitous STD telephone booths, which made long distance calls readily possible.

The barking of Rab woke me. I peeped out of my tent but could see nothing in the morning light. The sun was still behind the ridge in the direction Rab was facing. Giles, the schoolteacher, looked through his binoculars. ‘It’s an ibex… one … two … three…oh, there is a herd of them,’ he shouted.

The view was magnificent. Tall crags leapt from the slope where the ibex grazed; wisps of cloud swirled high among the cliffs, weaving a soft mantle against the now blue sky. The animals’ fawny-brown coats were camouflaged against brown rocks. Their short dark tails wagged. Enormous horns rose above their tiny heads, ending in sharp points. We thanked Rab for letting us see those magnificent creatures and offered him a special helping of food.

We were now in the remote Pin Valley of Spiti. White-washed villages appeared periodically, surrounded by patchworks of fragile fields. Harsh, rocky Mountains rose above them in singular walls. There were no trees or bushes, just stark ruggedness that formed its own beauty.

After eight days’ trekking from Kibber we were convinced that we are ready for an assault on Bhaba Pass. Tashi made breakfast a little earlier and before the morning sun had time to get too hot, we started our long march. In three hours we could have made half a day’s march but Bhaba was an altogether tougher and slower proposition.

The path was fairly flat for the first hour, turning into a climb about halfway up. And the further we climbed, the tighter the angle to the summit became. Almost four hours to the minute after we had set out, we hauled ourselves over the last boulders, high above the glacier, and found ourselves faced with one of the most supreme views on earth.

A cold wind was blowing on the pass and I was feeling heady owing to the altitude. The journey down the southern rim of Bhaba with deep snow was even more exhausting and precarious. I kept losing my footing on the loose surface, and when we finally reached the bottom, the waterfall down the mountain refreshed our sights. There was green everywhere, the monsoon clouds brought wisps of rain, the spray on our bodies glittering in the late afternoon sun. We followed a long, winding path through forests and across meadows of wild flowers, camping next to a stream. Later that day, while our tea and crispy pakoras were being prepared, we sat outside in the sun watching lammergeyers and imperial eagles circle overhead.

Suddenly Stephanie noticed that Rab was nowhere to be seen. The porters said that he may have died of cold. But I think Rab was too intelligent to go on. He may simply have turned back and headed for the last camp. There, having rested, he would have found his way back to the last village or other human habitation. This was the way in which Himalayan dogs exist: they hunt for themselves, find their own water, travel from village to village and master to master, earning their keep by playing watchdog.

Nevertheless, the sense of achievement was overwhelming and that night we built a bonfire and sat outside singing songs. I raised my mug of tea in a toast to my absent friends – much too weary to move and too smitten ever to leave.