Given the task definition and input, reply with output. 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.

The structure known as "Virgil's tomb" is found at the entrance of an ancient Roman tunnel (also known as "grotta vecchia") in Piedigrotta, a district two miles from the centre of Naples, near the Mergellina harbor, on the road heading north along the coast to Pozzuoli. While Virgil was already the object of literary admiration and veneration before his death, in the Middle Ages his name became associated with miraculous powers, and for a couple of centuries his tomb was the destination of pilgrimages and veneration.
During which time period did Virgil's name become associated with miraclous powers?