The "Estruendo"

Outside the official programme of the fiestas at around midnight the only peña which does not receive funding in all the Sanfermines performs: ¡t is the "Estruendo of Iruña". 

A multitudinous event in which hundreds of individuals come together each performing in accordance with his abilities -real or imagined- and imagination. Any noise-producing artefact will do: from the cornet to the saxophone, the trumpet to the horn, from the Basque flute to the txundas. Whatever. But even here there is a leadingfigure: the bombo, an enormous drum. This is the Estruendo, a deafening racket which puts the eardrums to the test as well as the walls, and hands or ear-m uffs!

The Estruendo is the popular expression of the purest and most radical sound of historic fiestas which are aboye all characterized by noise, from the bang of the rocket which opens them to the sad closing firework display of the traca.