My first sight of Kathmandu and the Himalayas was in 1960 as part of Lt Col Jimmy Roberts’s expedition – we made the first successful ascent of Annapurna II. At 7,937 metres, it’s a superb peak that’s just short of what mountaineers see as the magical height: 8,000 metres.

Arriving in Kathmandu was extraordinary. There was only one hotel, the Royal, an old palace run by a wonderful, eccentric Russian called Boris. There was also just one guesthouse, and practically no tourists.

Back then, the track from Raxaul to Kathmandu was the only road and there was little traffic. The city at that time was beautifully quiet … and incredibly beautiful.

There are hundreds of hotels and guesthouses now, of course, but I’d recommend the Kathmandu Guest House, which is relaxed, friendly and reasonably priced. Though if you want something more upmarket there is Hotel Yak and Yeti, which is close to the site of Boris’s Royal hotel!

It’s still a place of magic, with amazing views, such as the Kathmandu valley, but these days it is one of the most polluted cities on the planet: the roads are packed and Thamel, which I knew as a quiet district, is full of nightclubs and souvenir shops and stores selling outdoor equipment.

The best and quietest time to visit is during the monsoon season, from June to August. In fact, immediately after a rainstorm is when the views of the mountains and valley are most stunning. The rain keeps a lid on the dust that comes from all the rebuilding work being done since the 2015 earthquake.

My favourite view of Kathmandu is from Swayambhunath, the monkey temple on top of a little hill to the west of the city. It’s in a royal park that I recommend you reach the entrance of on a lovely 10-15 minute cycle ride from Thamel. Walk up the (steep) footpath and from the top, you’ll see the Kathmandu valley and Nagarjun Forest Reserve. I always say a prayer when I get to the top..

People think the earthquake destruction was worse than it is. The damage was appalling, tragically so in the Langtang valey, where an entire village was buried, but the Nepalese are resilient. You can still go to Nepal for a wonderful trek. They need trekkers.

The Garden of Dreams is magical and peaceful. There’s greenery to stroll around but there’s also a cafe where the delicious food is served outdoors in what is a beautifully restored Rana palace garden. The palace is gone but the gardens, which date to the 1920s, have been brought back to their best. It’s in the middle of the city but there are high walls around it and many trees so there’s not much traffic noise.

There are places I remember with great fondness, such as the original Rum Doodle bar. In the 1980s, it was where climbers would go for a drink. They’d ask you to sign your name on the ceiling – and I seem to recall them taking your hand print, too. There is still a Rum Doodle bar but it’s not the same place.

Kathmandu holds great memories of friends such as Elizabeth Hawley, who was a Reuters correspondent when we met in 1960, and who has kept details of every climber to scale Everest and has waylaid, for interview, every famous mountaineer who’s passed through: from Edmund Hillary to Ueli Steck (who sadly died in April).

I was lucky; I finally reached the summit of Everest in 1985, the last year the Nepalese only allowed one expedition on each route at a time. It was fantastic having it to ourselves. These days there are often 1,000 people at basecamp and perhaps 100 people on the south col making a bid for the summit.

Sir Chris Bonington’s new book, Ascent (Simon &Schuster £20), is out now. To buy a copy for £17, including UK p&p, visit guardianbookshop.com