FC Barcelona presents a mosaic with a difference for Saturday's Clásico

The mosaic is ready for Saturday. But the one for Barça v Madrid on December will be unlike any ever seen before. It’ll be animated! Honouring the Catalan tradition of castellers, a cardboard replica of a human tower will be built in the terraces, along with red and yellow stripes of the Catalan flag and the message Força Barça.

The over 90,000 people there to see the game at the Camp Nou will be called upon to generate an image that is sure to stun the whole world as it looks in from afar on the Clásico.

How the mosaic will work

In order to build the castle, everyone inside the stadium is going to have to play an active role. The cards must be raised in the right order, from the lowest upwards. We’ll explain how it works in three simple steps;

1) The supporters in the first tier should raise their cards first. They should do this when the club anthem (‘tot el camp…’) starts playing and keep it held in the air until the music has ended.

2) Next up are the supporters in the second tier. They should raise their cards when the anthem reaches the point that says ‘si del sud o del nord’. They too should then keep their cards in the air until the music ends.

3) The last group will be the supporters in the upper (third) tier. They should raise their cards when the song bursts into the chorus with the word ‘Blaugrana al vent’. They too should then hold their cards aloft until the end of the song.

There will be a reminder of the complete procedure on the video scoreboard and the stadium screens in the build-up to the match. There will also be an explanation printed on the back of each card.

What are castells?

The spectacular Catalan tradition of building human towers dates back to the early 18th century, originally in the Tarragona region although now they are a common feature at folk festivals and other celebrations throughout the country.

Over the years, the art of building such towers has developed spectacularly, and the heights reached by modern day casteller groups are astonishing. They can commonly reach up to nine or ten people high, and as the motto goes, reflect a fine combination of strength, balance, courage and level-headedness.

In November 2010, castells were declared by UNESCO to be amongst the Masterpieces of the Oral and Intangible Heritage of Humanity.