Callum Kerr, 17, visited the ATLAS cavern on 8 July, with this family and a representative from Make-A-Wish Foundation.

The Foundation, which grants "magical wishes to children living with life-threatening illnesses" helped coordinate the visit and grant Callum’s wish to visit the LHC and a high energy physics particle detector.

"This is so awesome, ATLAS is really big," said Callum who couldn’t stop smiling. He tells us of how he wanted to build a particle detector in his basement, the speech he gave in school about elementary particle physics, and how he would read books on quantum mechanics in the doctor’s office while waiting for medical treatment.

"Particle physics is so exciting, it doesn’t make any sense in a way that is logical but is still very logical. Quantum makes no sense but it makes sense, it gives that spin to understanding things," said Callum.

Callum and his family also visited SM18 and other facilities at CERN. This was the third time that Make-A-Wish Foundation brought a child to CERN to grant their wish to see the LHC and meet physicists.