Instructions: 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.
Input: The history of pubs can be traced back to Roman taverns, through the Anglo-Saxon alehouse to the development of the modern tied house system in the 19th century.
Output:
How far back does the history of pubs go back?