"We decided on instinct almost, that it was the right image for the record, but the intellectual reasons I haven't quite sorted out in my own mind. It has a spiritual aspect which this record has, and also a great deal of mystery which I like."
- The Edge on cover image for The Joshua Tree
Starting from Summer 2007 to Summer 2008, U2 had written and recorded 50-60 songs for a new record with Brian Eno and Daniel Lanois. 11 of these were released on 2009's No Line On The Horizon.