Complex sentence: While scouting a location for a film, Buscemi visited the Philadelphia Eastern State Penitentiary and found the building so interesting that he later provided the majority of the narration for the audio tour there.
Split into simpler sentences: While scouting a location for a film, Buscemi visited the Philadelphia Eastern State Penitentiary. He found the building so interesting that he later provided the majority of the narration for the audio tour there.