These incredible photos show the building of a human tower during the 25th Human Tower Competition in Tarragona, Spain on Sunday.
Members of the Castellers Joves Xiquets de Valls constructed the tower using precise techniques.
The 'Castellers' compete in groups, known as 'colles', at local festivals with aim to build the tallest and most complex human tower. The Catalan tradition is believed to have originated from human towers built at the end of the 18th century by dance groups and is part of the Catalan culture.
Castell (human tower) structures vary depending on their complexity and a castell is considered completely successful when it is loaded and unloaded without falling apart.
The highest castell in history was a 10-floor structure with three people in each floor. In 2010, castells were declared by UNESCO one of the Masterpieces of the Oral and Intangible Heritage of Humanity.
A castell is completed once all castellers have climbed into their designated places, and the enxaneta climbs into place at the top and raises one hand with four fingers erect to symbolise the stripes of the Catalan flag. The enxaneta then climbs down the other side of the castell before the remaining levels of castellers descend in highest-to-lowest order until all have reached safety.
Aside from the actual tower, other people are needed to form the pinya, the base of the castell. Members of the pinya act as a 'safety net' if the tower structure collapses.
The castell is built in two phases: the pinya is formed first and bands begin to play the traditional Toc de Castells music before the upper layers of the tower are built as quickly as possible in order to put minimal strain on the lower castellers.
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