William Lindesay and his wife, Wu Qi, show Mongolian herders postcards of a more familiar Great Wall, near Beijing. James Lindesay / for China Daily

"The Great Wall is an amazing sight, and it deserves to be seen in its best light," said William Lindesay in an interview with the BBC, after filming the wall from the air with the help of his family.

The Lindesays spent a total of 60 days tracing the world wonder with their drone in 2016, celebrating William's 60th birthday and his 30th year of living in China "for the wall", according to the BBC report.

William Lindesay is an Englishman living in Beijing, devoted to exploring, researching and protecting the mammoth construction.

Childhood dream

Lindesay was born in 1956, in Wallasey, a small town in north England. He studied geography and geology at Liverpool University.

His love of the Great Wall of China began when he was 11. The headmaster of his school asked students to put three books by the bedside: the Bible, a prayer book and an atlas.

Looking at the map of China in the atlas at one night, Lindesay came across the saw-tooth-like line that zigzags through the vast expanse of north China.

"I fell in love with it immediately," he said in an interview with China Daily. "I thought it would be a great journey, a great adventure if one day I could travel along it, from end to end."

Most people forget their childhood dreams and end up doing something else. "But I am one of those rare exceptions," Lindesay said.

Three decades for the wall

Lindesay's about 3,000-km solo run along the Great Wall began in 1987. It's an epic journey from the far west of China to the point where the structure meets the sea.

Running the length of the wall was a brave expedition, venturing into sparsely populated regions where there was little chance of help if the runner had a mishap.

The Briton endured extreme heat, giant blisters and chronic fatigue during the grueling run, which took place in two parts, during spring and fall, to avoid the more extreme heat of midsummer.

On one expedition out in the Gobi Desert, the explorer almost died from dehydration.

During another trip, Lindesay and his team ventured deep into the Gobi Desert of Mongolia, and located a previously unknown section of the wall.

In total, Lindesay estimates in an interview with China Daily, he has spent about 1,600 days of his life, or four full years, on the Great Wall in all seasons.

Lindesay's devotion to the wall is more than exploration. As of 2016, the 30th year of his journey along the Great Wall, he had published five books on the structure.

Lindesay is winner of the 1998 Friendship Award and 2008 Beijing Great Wall Friendship Award, according to the website of China's State Administration of Foreign Experts Affairs. He also received the Order of the British Empire from the Queen in 2006 for his contribution to cultural exchanges between China and Britain.

Campaigning for the wall's environment

Lindesay and his wife, Wu Qi, whom he got to know and fell in love with during his trips in China, had a farmhouse at the foot of the wall.

During his exploration, he noticed some sections of the wall were badly damaged and covered with litter. Modernization and development were making the situation even worse.

"Some people say it will take generations to change; I say we don't have generations of time. It's got to be much quicker," he said.

A name card is usually a small piece of paper with a person's name, address, telephone number and professional title printed on it. But Lindesay uses a garbage bag as his calling card. The cloth bag bears a set of nine simple guidelines in Chinese, which calls on people to observe while traveling or camping outdoors: "Take your own garbage home," "Pick up litter left by others," "Don't damage plants or flowers, or pick fruit" and lots more.

Lindesay always carries a garbage bag with him in the wilderness, picking litter along the way.

In 2001, Lindesay founded the International Association of Friends on the Great Wall, which uses volunteers from across the planet to collect garbage and protect the wall.

Since 1994, he has organized two major "Great Wall Clean Ups", according to the information from his personal website.

His wife Wu is president-assistant of the association, and is also concerned with the wall's environment protection.

Thanks to his contribution to the protection of the wall, Yulin city in Shaanxi province made him an honorary citizen in 2007.

Now a permanent Chinese resident, Lindesay lives in Beijing with his wife and two sons. He believes children are the most influential members of society.

Yes, not only influential, but also very creative. The drone filming idea came from his sons. The filming results, as he sees them, have been "out of this world". It's definitely a great gift for his 60th birthday.