NESTLED in the rolling hills of south Dorset is the chalk outline of a man whose identity remains unknown. Yet no expense is spared when it comes to preserving the Cerne Abbas Giant, and every decade scores of people turn out to touch up his shape. 17 tonnes of chalk is imported from a quarry in Salisbury and poured into the grooves, before volunteers press it down using heavy tampers until it becomes solid.

It’s certainly not easy work: “You do about 10 tamps and then you have to stop, stand up straight and let your arms rest,” Nancy Grace, an archaeologist at the National Trust, says. “You need plenty of people; that’s the key. But it’s going amazingly well.”

Over the years, the figure inevitably becomes indistinct, with the chalk turning discoloured and weeds covering the outline. This year, the National Trust dedicated 10 days to rejuvenating the famous giant to his former glory, inviting rangers, families and even local schoolchildren to get involved.

Jackie Green, a ranger from Shaftesbury, was part of the team removing the old chalk in preparation for the fresh material.

“There were about 30 of us scraping away the top layers,” she explains. “The chalk underneath is much cleaner, so the outline looked whiter even before it was replaced.”

The removed chalk was placed into large bags and winched back up the hill to waiting trailers, before being used to fill potholes in nearby farm tracks and paths.

Jackie added: “The giant is usually fenced off, so people have been really excited to get up close. It’s a once in a decade opportunity, and it's great to see people from all over the county - and country - getting involved.”

Amongst the volunteers were Michelle and her family from Poundbury.

“We moved to Dorset six months ago, so we’re newly local,” Michelle says. “The last time we came up here was winter, and it was snowing. We just thought it was a great opportunity. In the future, when we drive past, we can say, we were part of that. Hopefully the kids will remember it as they grow up.”

Hailing from slightly further afield were the Thorpe family from Worcestershire, who stumbled across the rechalking by accident and decided to sign up.

“We were on holiday in the area and planned to walk up to the giant anyway,” they explain. “We saw they were doing some work and asked what was going on, and the National Trust staff said we were more than welcome to join in - so here we are!

The children are actually enjoying it; it gets them off the games and into the fresh air. It’s good that they’re contributing to something that will be here for another decade before it needs doing again.”

Yet despite the enduring popularity of the Cerne Abbas Giant, its origins remain shrouded in mystery, with the first written record of the chalked figure dating back to 1694. In September 1919, the Pitt-Rivers family, who had owned most of Cerne Abbas since 1705, put the village up for sale at auction. The following year, the giant was donated to the National Trust, but both why and how it was created remain unknown.

Mike Clark is the chair of the Cerne Historical Society, and about as knowledgeable as it gets when it comes to theories abounding the giant.

"He could be pre-historic," Mike considers. "Perhaps an ancient Celtic God, or a depiction of the Roman God Hercules. Or he could be from the 1600s, around the time of Cromwell. But all the theories have got flaws. Whoever did it had to have access to resources and money, and had to have very strong motivation. It’s quite possible that none of the theories put forward are true."

So what does Mike consider to be most likely?

"I favour the more recent theories," he says. "I find it difficult to believe he can be very old, because it would have meant that the village would have had to look after him for 2000 years. We also had a monastery in the village for 500 years; I don't think the monks would have approved of a figure like this."

Surprisingly, Mike doesn't seem too keen to uncover the truth. "There is a feeling amongst many people in the village that we'd prefer him to remain an enigma," he says. "It adds to the mystery. If we did know, it would kind of spoil it."

From Tuesday, September 24 to Friday, October 4, the Cerne Historical Society will hold an exhibition in St Mary's Church, Cerne Abbas daily from 10am to 5pm to mark the centenary of the sale of the village. The exhibition will provide an insight into life during 1919, as well as information about the sale itself.

In the present, though, enthusiasts across the world can rest assured that the famous Cerne Abbas Giant, standing 60m tall and visible for miles around, will maintain his pride of place upon the hillside for at least another decade.