Will Self continues his 50 kilometre circumnavigation of the Large Hadron Collider at CERN just outside Geneva - entirely on foot.

Following the course of the Collider through the French and Swiss countryside, Will stops at regular intervals to descend to the tunnel below and view the experiments.

Invited to 'feel the wonder' of particle physics, Will is still baffled. He decides to issue an ultimatum to his CERN hosts.

Producer: Laurence Grissell.