Q: 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.
Carnaval de Solsona takes place in Solsona, Lleida. It is one of the longest; free events in the streets, and nightly concerts run for more than a week. The Carnival is known for a legend that explains how a donkey was hung at the tower bell − because the animal wanted to eat grass that grew on the top of the tower. To celebrate this legend, locals hang a stuffed donkey at the tower that "pisses" above the excited crowd using a water pump. This event is the most important and takes place on Saturday night. For this reason, the inhabitants are called "matarrucs" ("donkey killers").
A:
What is one of the longest free events in the streets?