What Is The Annapurna Circuit — 'The Best Long Distance Trek In The World?'

At least 39 hikers died on one of the world's most famous high-altitude treks after a freak blizzard hit the Annapurna Circuit on Oct, 15 during the height of Nepal's climbing and trekking season.

Thousands of tourists head to Nepal in October to swell the ranks of the elite climbers attracted by the country's high peaks. More than 400 of them were trekking the circuit when the snowfall hit, a tailend to Cyclone Hudhud which recently slammed into eastern India.

Many of the trekkers were caught off guard by what has been described as the deadliest spell of bad weather the region has seen. 

Nearly 400 hikers had been rescued after five days when the search for survivors was called off but it is not known how many more bodies may yet be recovered.

The disaster follows an avalanche on Mount Everest in April that killed 16 Sherpa guides.

(Editor's note: this article was first published on Oct. 16 and last updated with the most recent death toll on Oct. 19.)

Here is a brief guide to the Annapurna Circuit:

Where is it?

It is in central Nepal and passes Mount Annapurna, the world's 10th highest mountain.

How long does it take to trek?

It is 150 miles and takes about three weeks to hike.

How challenging is the trek?

Reasonably. But it is a "teahouse trek;" there are villages with guesthouse to eat and stay in along its full length, so you don't need to carry food or camping equipment, or hire porters. You'll be hiking, not climbing. It has generally been considered a safe hike and can be managed by the average outdoor enthusiast.

What is the route?

The trek begins at Besisahar or Bhulbhule in the Marshyangdi river valley and finishes at Birethanti near the Kali Gandaki Gorge. Most hikers go counterclockwise as that is considered the easier and safer direction. 

What is the highest point?

At the Thorung La Pass on the edge of the Tibetan plateau at 17,776 feet above sea level and 15,800 feet above the lowest point on the circuit.

What earns it the title of "the best long distance trek in the world?"

High-altitude Himalayan passes and pristine beauty. The trek crosses two river valleys taking hikers through terraced paddy fields, subtropical forest and the world's deepest gorge as well as circumnavigating the Annapurna massif with its numerous high peaks.

For how long has it been popular?

The circuit was opened to tourists in 1977, after the resolution of a guerrilla insurgency.

Has it changed since then?

Once the circuit was accessible only on foot. Now a dirt road has opened up parts of the area, and is changing what was the unique cultures of the various local peoples that live there. The advent of a road has, though, made parts of the circuit increasingly popular with mountain bikers.