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 architectural history of Estonia mainly reflects its contemporary development in northern Europe. Worth mentioning is especially the architectural ensemble that makes out the medieval old town of Tallinn, which is on the UNESCO World Heritage List. In addition, the country has several unique, more or less preserved hill forts dating from pre-Christian times, a large number of still intact medieval castles and churches, while the countryside is still shaped by the presence of a vast number of manor houses from earlier centuries.
Which medieval town is on the UNESCO World Heritage List?