This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

Tarragona has one of the region's most complete ritual sequences. The events start with the building of a huge barrel and ends with its burning with the effigies of the King and Queen. On Saturday, the main parade takes place with masked groups, zoomorphic figures, music and percussion bands, and groups with fireworks (the devils, the dragon, the ox, the female dragon). Carnival groups stand out for their clothes full of elegance, showing brilliant examples of fabric crafts, at the Saturday and Sunday parades. About 5,000 people are members of the parade groups.
What do the events of Tarragona start with?