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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.

With the collapse of Roman rule in the early 5th century, London ceased to be a capital and the walled city of Londinium was effectively abandoned, although Roman civilisation continued in the St Martin-in-the-Fields area until around 450. From around 500, an Anglo-Saxon settlement known as Lundenwic developed in the same area, slightly to the west of the old Roman city. By about 680, it had revived sufficiently to become a major port, although there is little evidence of large-scale production of goods. From the 820s the town declined because of repeated Viking invasions. There are three recorded Viking assaults on London; two of which were successful in 851 and 886 AD, although they were defeated during the attack of 994 AD.
Output:
What area continued to exist after Londinium was abandoned following the end of Roman rule?