The only admissible evidence upon the true height of giants is that of recent date made under impartial medical supervision."

These were the words of Norris and Ross McWhirter, the founders of Guinness World Records, in 1955. They went on to dismiss claims for legendary giants such as the biblical Og, King of Bashan (allegedly 9 Assyrian cubits, or 494.03 cm/16 ft 2.5 in tall), citing "confusion of units".

The twins then named Robert Wadlow as the tallest man "of whom there is irrefutable evidence".

When last measured on 27 June 1940, the mild-mannered American stretched a staggering 2.72 m (8 ft 11.1 in) tall.

Perhaps surprisingly, Robert entered the world no differently to most babies. He was born on 22 February 1918 to two regular-sized parents, weighing an unremarkable 3.85 kg (8.7 lb).



But he rapidly started to shoot up, reaching an incredible 1.63 m (5 ft 4 in) by the age of five, by which time he was already wearing clothes intended for teenagers.

Toddler in teenager's clothing

Aged eight, he overtook his 5-ft 11-in-tall (180.3-cm) tall father, Harold F Wadlow, and towered over his four younger siblings.
When most children were still being carried by their parents, Robert was able to lift his father up the stairs of their family home.

Robert's incredible height caused a number of medical issues however, which worsened as he grew older – and taller. Yet as a young boy, he tried his hardest to get involved in the same activities his peers were doing.

For example, he became a Boy Scout at the age of 13, and had a customised uniform, tent and sleeping bag.



Robert passed the 2.45 m (8 ft 0.5 in) mark by the age of 17, making him – unsurprisingly – the tallest teenager ever.

In 1936, the gentle giant graduated from high school and enrolled in college with the intention of studying law.

Celebrity career

However, later that year he would embark on a tour with the hugely popular Ringling Brother Circus, which saw the giant earn worldwide fame.

When asked in a radio interview if he was annoyed when people stared at him, he calmly replied, "No, I just overlook them."

The quiet, unassuming man took his new-found celebrity status in his stride, and used it to earn money from public appearances.



He also did a promotional tour with the International Show Company (now INTERCO), which agreed to make him shoes for free.

This was a blessing for Robert, who had whopping 47-cm-long (18.5-ft) feet – the equivalent of a US size 37AA (UK size 36, roughly a European size 75) – the largest feet ever. His shoes could cost as much as $100, equal to $1,500 (£1,026) in today's currency.

The Alton Giant also boasted the largest hands ever, measuring 32.3 cm (12.7 in) from the wrist to the tip of his middle finger.

But what caused Robert's extraordinary height?

Pituitary gigantism

Doctors examined Robert and realised that his exceptional size was caused by hyperplasia of his pituitary gland. This condition causes an abnormally high level of the human growth hormone and Robert was never given any treatment to stop it.

Dr Donald Rau, Medical Consultant, Guinness World Records explained: "Robert Wadlow escaped the attention of surgeons, as they were not confident enough to operate on him. Therefore he might remain the tallest man for a very long time."

With a staggering peak daily food consumption of 8,000 calories, he actually continued to grow taller right up until his death.

Since then, medical technology and treatment has advanced significantly and people who suffer from pituitary gigantism – such as Sultan Kösen, the tallest man living as of 2017 – are able to have surgery to halt the production of the growth hormone.

Robert's condition caused him to have difficulty getting around – he had leg braces and a walking stick, but never used a wheelchair.



Wadlow's death

Sadly, it was Robert's legs that caused his premature death, aged just 22 years old.

He died at 1:30 a.m. on 15 July 1940 in a hotel in Manistee, Michigan, as a result of a septic blister on his right ankle caused by a brace.