Bhutan only opened to the outside world in 1974. Yet, one region remained closed for decades afterwards, and is one of the Himalayas' best-kept secrets.

It's 05:00 and 100 people have gathered in the courtyard of Lhakhang Karpo, a 7th-Century monastery at the base of three sacred mountains in Bhutan's secluded Haa Valley.

Incense plumes swirl in the mist. Pink rice porridge with Sichuan pepper steams in vats. Low, thrumming chants hum through me. Then: drums. A blast of dungchen trumpets. Crackling, cawing victory calls and – pow!

I jump.

A gunshot.

"It's only a blank," Rinchen Khandu, the town mayor, assures me.

This isn't your typical Buddhist festival. I'm at the Ap Chundu Lhapsoel, a 10km procession held every 1 November in honour of the valley's warrior deity who helped locals defeat invading Tibetans in the 17th Century. It's the nation's longest chipdrel (ceremonial procession) – and the only one where tourists are welcomed – yet few visitors have ever heard of it. In a way, the festival is a metaphor for Haa itself.

Located along Bhutan's rugged western frontier near the Tibetan border, Haa is one of the smallest and most secluded districts in the world's last Buddhist kingdom – and one of the Himalayas' best-kept secrets.

Bhutan famously cut itself off from the outside world for centuries to protect its culture, only allowing foreign tourists in 1974. But Haa – because of its sensitive position along the Tibetan border and its use as a military training ground for the Royal Bhutan Army until the mid-1990s – remained closed for decades longer, opening only in 2002. For years, it was a hermit region within a hermit kingdom.

Today, the diminuitive district is one of Bhutan's most biodiverse corners, home to rolling emerald mountains where pine forests spill down the slopes. Blue sheep drink from glacial lakes, red pandas hide in bamboo undergrowth, snow leopards roam the ridgelines and blue poppies (Bhutan's national flower) bloom in the higher elevations come summer.

Because of its long isolation, Haa is also where Bhutan's Indigenous Bon traditions remain strongest and its culture is still shaped by guardian deities. Unlike other parts of the country that now have Western hotel brands, Haa has just a handful of homestays, heritage inns and local eateries. As a result, the valley is a veritable time capsule, offering a glimpse of Bhutan before it opened up.

How to visit Haa Valley

Visa: All tourists are required to have a visa (£30/$40) and pay a daily Sustainable Development Fee (£75/$100) to help the government fund free healthcare and education.

When to visit: Spring for the Haa Spring Festival, summer for the warm weather, autumn for festivals (Haa Tshechu, Ap Chundu Lhapsoel) and winter for Haa's New Year, typically in December.

How to get there: Fly to Paro and drive to Haa via the Chelela Pass or from Thimphu via the recently upgraded Chuzzom-Haa highway.

How to visit: You'll need a car and driver and should hire local guides for day hikes.

Where to stay? Experience village life at

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