If you’ve ever seen NBA players Manute Bol or Gheorghe Muresan towering over their teammates and opponents, you’ve probably already guessed the 7 feet 7 inches players are the tallest in NBA history. Does that make them the tallest men of all times? Not even close. The honor goes to Robert Wadlow. There may have been taller men on less traveled continents or from hidden societies. But Wadlow is indisputably the tallest man in history according to documented evidence, and still holds the Guinness World Record some 80 years after his death in 1940. He had a rare medical condition that couldn’t be treated in his lifetime. Here’s how a very tall man lived his short life.

The guy who grew to 8′ 11″

Born Feb. 22, 1918, in Alton, Illinois, Robert Pershing Wadlow was an average size baby. But after his first few months on earth, he just grew and grew. Imagine the neighbor’s surprise when the baby of six months already weighed 30 pounds! Little Robert suffered from an overactive pituitary gland that gave him massive amounts of human growth hormones. He was the oldest child in the family and all his four siblings were normal height and size. Wadlow lived just 22 years, dying July 15, 1940. At the time, he was still 8 feet 11 inches and still growing. Oversized equipment made just for him was the theme of “the Alton GIant’s” life. At age 8 he was taller than his six-foot father and required a special desk at elementary school, for example. As a teen, he attained 7 feet 4 inches and it took 14 yards of material to make his Boy Scout uniform. (Yes, he was and remains the world’s tallest Boy Scout, too.) Wadlow required a special train seat when he began touring with the Ringling Brothers Circus after high school. But even then he hadn’t reached his full height: He was “just” 8 feet 4 inches.

The health risks of hyperplasia

Wadlow’s off-the-chart growth drew a lot of attention for the quiet young man. Along with touring with Ringling, he was a spokesperson for the International Shoe Company. They made his size 39AA shoes, too. He was featured on a newsreel in 1935 and was the subject of a Robert Ripley cartoon twice in his lifetime, in 1926 and again in 1929. But the condition that made him famous was also very hard on Wadlow’s health and caused his premature death. Basically, the rest of his body could not support his immense growth. While he was not fat, just very tall, he did weigh more than 400 pounds and had to get leg braces at age 20. With his height came poor circulation, so he also could not feel sensation in his feet, even when blisters formed. He died when one of the blisters developed into an infection that did not heal. At death, he weighed 490 pounds and doctors of the day surmised that he might have reached 9 feet tall if he had lived longer. His casket weighed more than 1,000 pounds and required 12 pallbearers. Wadlow had built up quite a following as he visited more than 800 towns and 41 states for the shoe company, and more than 40,000 people attended his funeral.

The legend of Robert Wadlow

Wadlow is gone, but certainly not forgotten. He was one of just eight men who ever exceeded 8 feet in height and his tallest man ever record still holds. Ripley’s Believe It or Not! keeps the legend alive with models of Wadlow in each of its worldwide “odditoriums.” People can get close enough to see what it would have been like to stand next to the tallest man in the world. But as for what it’s like to stand 8 feet 11 inches and still be growing, Wadlow alone knows what that’s like.