Spanish photographer David Oliete shot these incredible photos of the 2012 Concurs de Castells, the world’s largest Human Tower Competition that takes place in Tarragona, Spain. The event saw participation of 32 teams from around Catalonia and an audience of over 20,000 people. During the competition, the higher and difficult to build a tower is, the more points a team gets. Every human tower is usually between six and ten levels high. Teams are made of between 100 to 500 women and men. Young and light members form the top of the tower while heavier members form the base. The “castells” have also been one of the most important cultural traditions in Catalonia for more than 200 years. “Strength, balance, courage and common sense” is their motto. In 2010, the castells were declared by UNESCO to be amongst the Masterpieces of the Oral and Intangible Heritage of Humanity”. Insanity.