Torquay Girls Grammar School B Team, the first all-female team to finish the 2015 Ten Tors Challenge. Photo: Corporal Daniel Wiepen

Almost 2,000 young people completed a gruelling test of their trekking endurance and navigation across Dartmoor.

Nine out of 10 participants in the Ten Tors Challenge managed to finish the course, held over two days across the national park.

The start, early on Saturday, saw 2,190 teenagers set off from Okehampton camp in the Army-organised event, being run in its 55th year in their quest to cover 35, 45 or 55 miles across the northern slopes of Dartmoor, carrying up to 15kg of tents, bedding, food, water, clothing and other equipment as they went.

They trekked unaided, without the help of adults, camped overnight on the moor in a self-sufficient journey across the moor, as many of them have trained to do since before Christmas.

The Churcher’s College Combined Cadet Force 35-mile team from Hampshire was the first to arrive back at Okehampton Camp, emerging out of the mist shrouding the tors.

The adventure started in heavy rain at Okehampton Camp with two 105mm light guns from Plymouth’s 29 Commando Regiment Royal Artillery being fired at 7am on Saturday. And for the first time, the Commando gun crews ‘fast roped’ from one of two Sea King helicopters from 848 Naval Air Squadron based at RNAS Yeovilton, before the aircraft carried out a flypast for the hundreds of families and other spectators who had gathered to watch the start, despite the weather.

It was a chance to say farewell to the Sea Kings, which are being replaced soon as they have reached the end of their service life.

A short time later, 30 Jubilee Challenge teams with a range of disabilities set off on their own adventures across Dartmoor, before finishing back at Okehampton Camp from 11am onwards to cheers from the gathering.

The Ten Tors also provides the armed forces with an opportunity to practise life-saving civil contingency responsibilities to enable the military, assisted by the emergency services including the British Red Cross and the Dartmoor Search and Rescue Group, to be ready to help when they are called upon during a national emergency.

Each team is monitored as they walk across the open moor by the multi-agency Ten Tors operations room via a GPS tracker which not only gives their location, but also enables them to contact the organisers in an emergency.

Brigadier Jez Bennett, in charge of the event for the first time, said: “It has been a hugely emotional experience for everybody.

“It’s hard work for the competitors, it’s hard work for the agencies and it’s hard work for us to get it right. It’s a fantastic achievement [to complete the event]. I know some of them are exhausted. Most of them say they want to do it again; some of them say they’ll never do it again.

“It has been really hard work and they should be proud; we are.”