US Edition 
Stephen Wiltshire, the human camera who drew London from memory
Flying in a helicopter along the Thames, Stephen Wiltshire memorised the appearance and position of hundreds of London's buildings.
Over the next five days he drew the panorama in fine detail on a 13ft curving canvas, never referring to notes, sketches or photographs.
All buildings were drawn to scale and in position, with the precise number of floors and other structural features included on landmarks such as the Swiss Re tower, known as the Gherkin, and Canary Wharf.
Wiltshire, 33, told the television channel Five - which charted the challenge for its documentary, Extraordinary People: The Human Camera, that he was "thrilled" with the result.
The challenge marks another chapter in his remarkable life, 30 years after being diagnosed as autistic.
As a boy he could not speak and threw tantrums in frustration at not being able to make himself understood.
The only thing that seemed to pacify him was being given a pencil and paper. Soon his unique gift became obvious to others.
Aged six, he shocked a family friend by drawing an accurate sketch of the facade of the department store Selfridges in a style well beyond his years.
At eight he sold his first drawing, of Salisbury Cathedral. Drawing gave him the motivation to communicate with others and the ability to lead an independent life.
Teachers at Queensmill, a school in Fulham for special needs children, first got him to speak by taking away his materials, forcing him to shout "paper!"
Soon he developed language skills, picking up words related to his twin obsessions - drawing and buildings.
Prof Simon Baron-Cohen, director of Cambridge University's Autism Research Centre, said: "We can speculate as to why Stephen chose buildings as his first topic of drawing in that buildings stay the same every time you look at them.
"People with autism like sameness, they like repetition, they like patterns in the environment."
Wiltshire was awarded an MBE for his services to art in 2006 and has his own gallery on Pall Mall, central London. His originals sell for thousands of pounds.
• Extraordinary People: The Human Camera is on Five, Wednesday April 9, at 9pm.