There is something rather deep-rooted about our desire to produce buildings choreographed to focus the attention of the spectator on the activities within. The use of a circular geometry to achieve this goes back a long way, from Stonehenge and Celtic stone circles to the Pantheon and the Colosseum, via Santa Maria del Fiore to St Peter’s Square in the Vatican City, to bullrings, soccer stadia, athletics tracks and velodromes.