Every summer in Catalonia, crowds gather in town squares to watch something remarkable: castells, or human towers. These breathtaking structures can reach up to nine  or ten stories high, with sometimes hundreds of people moving together in tandem. The word castell means castle, and just like bricks in  a castle, every person is a vital part of its structure.

A Living Catalonian Tradition

Castells began in the late 18th century in the town of Valls, near Tarragona. Originally part of a folk dance called the Ball de Valencians, the tower soon became the main event. Over time, the tradition spread, and local teams known as colles castelleres began to compete to build taller and more complex structures.

Each team wears a distinct shirt colour such as red, green, or blue, and a long black sash called a faixa. The faixa supports the lower back and provides a grip for climbers. At the tower’s base, the pinya (meaning “pineapple”) forms a strong foundation. Above them, layer after layer of castellers climb carefully until finally, the smallest child, the enxaneta, reaches the top, raises one hand, and salutes the crowd. This moment, called the aleta, marks success.

Though it looks like a test of strength, building a castell is truly a lesson in trust, timing, and teamwork. Each participant must know their exact position and movement. The base supports the weight of those above, while the top relies on the stability of the foundation. The entire tower is an exercise in balance, both physical and social.

Did you know?...

Few people know that the youngest castellers can be as young as five, but always with safety in mind. Since 2006, helmets have been mandatory for child climbers, and all movements are choreographed to avoid risk.Another surprising detail is that the music of the gralla, a traditional Catalan instrument, acts as a communication system. Each melody signals the stage of the climb, when to begin, when to brace, and when the top has been reached.

A Symbol of Unity

In 2010, UNESCO recognised castells as part of the Intangible Cultural Heritage of Humanity, calling them a symbol of social cohesion and solidarity. Indeed, people of all ages, jobs, and backgrounds join in. In a colla castellera, it doesn’t matter who you are, only that you work together.

When a tower falls, the crowd doesn’t boo or criticise the castellers. In fact you will hear applause instead. A fall is not viewed as failure, but as part of the process, a sign of courage and collective spirit. And it takes a lot of bravery to climb nine or so stories!

The famous motto “força, equilibri, valor i seny”, meaning strength, balance, courage and common sense, captures what the tradition represents: the Catalan spirit of unity and determination.Castells are not just a performance; they are a living reminder that even the tallest towers are built on trust.