Marshall became Phil Parkinson's fifth summer signing earlier this week before making the journey north with his new team-mates to City's Scottish base just north of Glasgow.
Speaking at Tuesday's friendly with Motherwell at Grangemouth Stadium, Marshall explained his reasons for joining up with the Bantams.
Supporters can hear Mark's thoughts on moving to City by clicking on the video link below.
Bantams PlayerHD subscribers can see the full video interview with Mark by clicking HERE.
Fans can subscribe to Bantams PlayerHD by clicking HERE.