The world's tallest man, Sultan Kosen, has made his first visit to Australia, proving to a group of schoolkids that giants really do exist.

"I really love Australia," Mr Kosen said during a visit to Amity College in south-west Sydney.

The 31-year-old farmer from the city of Mardin in south-eastern Turkey stands at a whopping 2.51 metres (8 feet, 3 inches).

Guinness World Records crowned him the world's tallest man in 2009.

"Getting the record has opened lots of doors for me," Mr Kosen said.

"I get to travel all over the world."

Visiting Sydney for the Anatolian Turkish Festival held over the weekend, Mr Kosen wowed Amity College students.

"It was amazing. I really liked seeing him and it was very nice," one student said.

Head principal Deniz Erdogan said the students felt privileged to be the only school visited by the big man.

"It was a fantastic experience for the students and staff," he said.

"He [Mr Kosen] has strong messages about education, and it's great to see he values the diversity in this school."

No extra legroom for the extremely tall

According to the Guinness World Records, Mr Kosen is one of only 10 people known to have reached eight foot or more.

However, being extraordinarily tall is not without its disadvantages, some significant.

"The flight from Turkey was difficult for me," Mr Kosen said.

Sultan Kosen, eight feet three inches tall, stands beside the ABC's Mohamed Taha, who is six foot. ( ABC )

"Even though I flew business class, the seats were too small and so were the amenities."

He added: "Growing up was very difficult and very challenging. I couldn't fit in a car or find clothes that fit me. I was unable to attend school because of my health conditions."

Mr Kosen's incredible growth began at the age of 10.

His growth is caused by a condition known as pituitary gigantism, involving an over-production of growth hormones.

In August 2010, Mr Kosen had revolutionary surgery in the United States on the tumour affecting his pituitary gland.

The tumour was successfully removed and he stopped growing.

"The surgery saved my life," Mr Kosen said.

And despite the discomforts, Mr Kosen is comfortable in his skin.

"It's a good feeling to be the tallest man in the world," he said.

"Out of seven billion people, I have this unique title."