The video below shows the Botafumeiro in action during one of the pilgrims masses.
The Santiago de Compostela Botafumeiro is the largest censer in the world, weighing 80 kg and measuring 1.60 m in height.
It is normally on exhibition in the library of the cathedral, but during certain important religious events it is attached to the pulley mechanism and filled with 40 kg of charcoal and incense.
In the Jubilee Years, whenever St James’s Day falls on a Sunday, the Botafumeiro is also attached in all the Pilgrims’ Masses.
Eight red-robed tiraboleiros pull the ropes and bring it into a swinging motion almost to the roof of the transept, reaching speeds of 60 km/h and dispensing thick clouds of incense.
One irreverent explanation of this custom, which originated more than 700 years ago–although incense has been used in Catholic ritual from the earliest times–is that it assisted in masking the stench emanating from hundreds of unwashed pilgrims. Read more on Santiago Cathedral.