After arriving at Charles de Gaulle airport in Paris, he was unable to prove his identity or refugee status and was detained in the waiting area for travelers without papers.
He lived, studied, slept, and talked with the airport staff from August 26, 1988, to July 2006.
His bizarre story inspired multiple movies, most notable ‘The Terminal’ staring Tom hanks.
Source: https://historicflix.com/mehran-karimi-nasseri-the-man-who-lived-in-an-airport-for-18-years/