…a circle has no beginning and no end. It represents rebirth and regeneration, continuity and infinity. From wedding rings to stone circles, in poetry, music and the trajectories of the planets themselves, circles and loops are embedded in our imaginations.

In this five-part series poet Paul Farley goes walking in circles in five very different ‘loopy’ locations. He visits a stone circle, a roundabout and a particle accelerator to ask why human beings find rings and circles so symbolic, significant and satisfying.

The earliest civilisations were drawn to the idea of closing a circle and creating a loop; in human relationships we’d all rather be within the circle of trust; and in arts and music our eyes, ears and minds are inexorably drawn towards loops and repetitions.

Paul has circular conversations with mathematicians and physicists, composers and poets, each one propelling him into a new loop of enquiry. And that’s because a circle has no beginning and no end…

This week Paul is in the loop at the Grand National rollercoaster which has been drawing thrill-seekers to Blackpool Pleasure Beach for nearly 90 years. He talks to Andy Hine from the Rollercoaster Club of Great Britain to explore this addiction to ‘airtime’. Paul also discovers that the Grand National isn’t just an entertainment. It’s also a mathematical phenomenon: a Möbius Loop. Another rollercoaster fan is composer Anna Meredith. Paul meets her to reflect on the importance of loops and repetition in her music. Show less