The basic castell structure is formed by the pinya, the base of the tower that serves to counterbalance the tower’s weight and to cushion the fall in case of collapse. The next stage is the tronc (“trunk”), the vertical part of the tower visible from the segons (“seconds”), the second story of the tronc, to the dosos (“twos”), a level consisting of two people. The tower is topped by the aixecador (“riser”) or acotxador (“croucher”), the last level before completing the tower with the enxaneta (the child who forms the uppermost level). For more difficult constructions, a folre (“reinforcement”) may be located like a smaller pinya on top of the base pinya, which may also be topped by manilles, reinforcement for the third and fourth levels that is built on top of the folre. When the tower has no reinforcement or less support than usual, it is called a castell net (clean tower) or a sense folre (no reinforcement).