Since its start in the 1973, Greenbelt has grown from a youth event, to which 1500 people came, to seeing crowds of nearly 30,000 in the mid-1980s. It now has a focus that is much broader than youth. The festival regularly attracts the biggest names of Christian music, and many mainstream musicians with Christian beliefs or connections. Those that have played the festival in the past include U2, Cliff Richard, Bruce Cockburn, Steve Taylor, Daniel Amos, Over The Rhine, Iona, Amy Grant, and Miles Cain.
Greenbelt is a venue for Christian teaching and discussion, and has attracted some the best Christian speakers in the world, including the Archbishop of Canterbury, who is now the festival's patron. It frequently tackles controversial themes, and invites speakers from all parts of the world. It is also a showcase for Christian performing arts, visual arts and alternative worship.
Greenbelt has been staged at different venues in its history, and in 2004 is at Cheltenham racecourse.