"I thought 'pop' was a term of abuse, it seemed sort of insulting and lightweight. I didn't realise how cool it was. Because some of the best music does have a lightweight quality, it has a kind of oxygen in it, which is not to say it's emotionally shallow. We've had to get the brightly coloured wrapping paper right, because what's underneath is not so sweet."
- Bono describing the difference between the "surface" of the songs to "what lies beneath".
The cover art for No Line on the Horizon is a photograph of Lake Constance, taken by Japanese photographer Hiroshi Sugimoto; titled Boden Sea, it is one of 200 pictures in his Seascapes collection. The image was the inspiration for Bono's lyrics on the track "No Line on the Horizon".