It can be difficult to raise a mountain. Catalonia has castells, massive towers of humans that can reach jaw-dropping heights.

The tradition of gymnastic and human tower–building in Spain dates back to the early 18th century and is still practiced today. castells have been gaining in popularity for the last several decades, unlike other ancient sports which have all but disappeared. A number of teams are active in the region.

Teams battle to build the tallest castell and then dismantle it in a controlled fashion. The human is playing a game called Jenga. The pinya is the strength of dozens of individuals woven together to form a foundation, as shown in the image above, which was taken during a competition in Tarragona.

The tronc is the midsection of the tower and is created by a small group of castellers. Each level stands on the shoulders of the one underneath it. The top tiers are usually made up of children or women. A single enxaneta climbs to the tippy-top of the human pyramid to signal to the crowd and judges that the castell is complete. In addition to the number of levels, castells are evaluated by the orderliness of the process, starting and finishing. The upper layers of the castell are lifted into the air by the next level of castellers.

A castell—seven layers, if you're counting—takes shape in Barcelona.
A castell—seven layers, if you’re counting—takes shape in Barcelona. Joan Gil/Public Domain/Wikimedia

Every aspect of building a skyscraper is carefully managed. There is a specific name for each position and level. The castellers have waists that are used to support the back and also as hand and footholds for teammates scrambling up or down the tower. The rhythm of the traditional music played during construction helps to keep castellers on their toes. Even though the towers are usually built in the middle of a town square, serious injuries and deaths are rare.

The knowledge needed to create castells is passed down from generation to generation according to the organization. Each new generation builds upon the previous one.