Catalonia is known for its sea-side markets (la boqueria), gothic architecture -- championed by Antoni Gaudí -- and sparkling white champagne (cava). The territory boasts its own language (Catalun), flag, and governing body (Generalitat). But perhaps the most dramatic display of Catalonian culture comes from the people themselves, who literally and figuratively band together to build human-towers (castells).

“The human tower is a metaphor for the Catalonian identity,” says Montserrat Rossell Xicola, a journalist and producer of the film Castells, created by Autobahn, a London-based production company. Xicola grew up in the Vallès Oriental region of Catalonia and always admired castells Her brother temporarily competed though she never participated herself.

Observers say the practice is symbolic of togetherness, the elimination of class differences, and Catalonia’s welcoming atmosphere, Xicola says. “You can step on your boss in a human tower, you cannot do it outside this.”

“It's a very important cultural heritage in our country,” she says.

Castells are constructed by Catalans of all ages, who stack themselves on top of each other by climbing up backs and shoulders. The practice was first documented in 1801 as a cultural activity and became a competition in the 1980s. Declared an Intangible Cultural Heritage of Humanity by UNESCO in 2010, castells are recognized as having a “rich cultural diversity” and significance within Catalonia.

There are currently between 60 and 70 castell teams (colles) in Catalonia, some of which appear at large, bi-annual competitions in Tarragona, Spain. The teams are awarded points based on how high they can build their towers without falling. The most ambitious castells stretch ten levels high, each level the height of a person. In 2018, 42 teams competed at Tarragona.

“So little people know about [Castells] outside of Catalonia,” says Pedro de la Fuente, co-filmmaker of Castells. “We felt so lucky to be not only witnessing it but filming it. It's equivalent to going to Egypt to see the pyramids or going to Peru to see Machu Picchu.”

For some practitioners building castells is a demonstration of nationalism. Nationalistic interpretations surfaced after the 1975 death of Spanish dictator Francisco Franco. Franco banned many inherently Catalonian and Spanish practices during his rule from 1939 to 1975, such as speaking the Catalun language, waving the Catalonian flag, and observing Catalonia’s national holiday, Diada. Likewise, Franco threatened castells, allowing only one of the teams to practice.

“When you're coming out of a dictatorship, you have nothing,” says Pablo Giori, a historian based in Barcelona. “They were looking for new things and [found] new things in the festivities of the towns. They were really connected with this idea of experience, that everyone became part of it.”

Giori, a native of Argentina, began studying castells 11 years ago, after moving to Barcelona. Originally captivated by the structures themselves, he says he realized that “the human towers were not the most important thing. The most important thing was this idea of community, this idea of a nation.”

When he talks about nationalism, Giori is not referencing a specific political party, not all members of castells uphold the same political affiliations, but an intimate connection within Catalonia’s civil society. Historical hardships, like economic crises, motivate the people to support each other, he says.

“When you have problems, the best way to find a solution is by having a strong community,” Giori adds.

Large castells contain five main levels. The base is called the pinya, followed by the folre, the manilles, the tronk, and the pom de dalt. The tronk is the vertical structure in the center of the castell that holds the most weight. The strongest men make up the bottom of the tronk, followed by stronger but lighter women. A small child known as the enxaneta climbs to the pom de dalt.

“We saw it as a poetic reflection of the society,” says James Worsley, co-filmmaker for Castells. “You have the elders holding the weight of the younger community on their shoulders.”

The enxaneta is usually a girl between 7 and 10-years-old. One teenage participant told Worsley that she started castelling when she was only 4-years-old. She must be light, nimble, and at times, fearless.

As the enxaneta begins her ascent, a hush falls over the crowd. The silence lends itself to different emotions: excitement, that she may succeed; fear, that she may fail; and “a sense of importance in the air,” de la Fuente says. “Something special.”

“You don't know where the tower is going to end. You don't know how many people she's going to climb,” he adds. “There's an emotional thing.”

Emotions peaked in 2006, with the death of enxaneta Mariona Galindo, who suffered fatal injuries after falling from a castell. Since the incident, colles implement safety precautions like requiring children to wear helmets and providing a net during rehearsals.

Women and children were not included in colles until 1980s. Since their addition, castells have become lighter and grown taller.

But there may be a physical limit to castell’s growth, Giori says. Already at ten levels, the people must brainstorm how to increase their influence horizontally across Catalonia while being unable to rise vertically.

“At some point, you can’t make it bigger and bigger every year,” Giori says. “There is a physical limit.

They have to find another motivation for doing human towers.”

For now, their cultural bond is enough to keep building.

“It's a very close-knit activity,” de la Fuente says. “You have people who are going to be breathing in your face, and you're going to be grabbing hold of other people's bodies. When they do this, it's almost like they become one.”