"One Tree Hill," by U2. U2360 Tour | Chicago, IL, USA | 5 July, 2011

"One Tree Hill," by U2. U2360 Tour | Chicago, IL, USA | 5 July, 2011

As an unplanned conclusion to the night's concert, Bono decided to perform "One Tree Hill" to mark the 25th anniversary of on of the band's friends, Greg Carroll.