Thomas Heatherwick’s design of the Olympic Cauldron has been one of the most closely guarded secrets of the whole Ceremony.

When the competing delegations arrived in London, they each received a copper petal – inscribed with the name of their country and the words ‘XXX Olympiad London 2012’. They carried these petals during the Athletes’ Parade before laying them down.

The seven young Torchbearers move towards the centre of the field of play and ignite a single tiny flame within one of the copper petals on the ground, triggering the ignition of more than 200 petals. The Cauldron’s long, elegant stems gently rise towards each other and converge to form one great Flame of unity – a symbol of the peaceful coming together of nations that is the Olympic Games.

The Cauldron will be moved to take pride of place in the Olympic Stadium within the eyesight of competing athletes – echoes of its location at Wembley for the London 1948 Games.

At the end of the Games, each team will take their petal home and the London 2012 Cauldron will cease to exist. Like a flower that only blooms for the duration of the competition, it’s a temporary representation of the extraordinary transitory community that is the Olympic Games.

Brightness falls from air.
Light comes out of the ground.
A single lens – two hundred lights dance round it.
Ten billion eyes look into it.
But not one eye sees me – hidden in its heart.
Until two hundred lights converge.
At the lens’ focal point.
Kindling me to flame.
The light of all ten billion eyes.
One fire for every nation.
Brightness falls from air.
Light comes out of the ground.

Answer modern riddle: cauldron

Listen to the wonder of his birth.
Silent husband stroke silent wife.
This one comes roaring into life.
In battle he is strong and wild.
But a maid may make him mild.
Feed him well and he will feed you.
Feed him too much and he will eat you.

Answer 1,000-year-old riddle: fire.