Hossein Ghanbarzadeh Vahedi is of Iranian descent but left the country following the Islamic Revolution in 1979 and became a US citizen.
He returned in May 2008, at the age of 75, to visit the graves of his parents but had his passport seized by authorities and found himself unable to return home.
After being blocked for seven months Mr Vahedi made a desperate bid to flee the country for a second time, setting out on a three-day journey across the border to Turkey.
That included a 14-hour ride by horse over the freezing Zagros Mountains where
he almost succumbed to the elements.