Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Historic Centre of Brugge' has mentioned 'City walls' in the following places:
Occurrence Sentence Text Source
With the reawakening of town life in the twelfth century, a wool market, a woollens weaving industry, and the market for cloth all profited from the shelter of city walls, where surpluses could be safely accumulated under the patronage of the counts of Flanders.
The 12th century city walls marked the boundaries of the medieval city.