Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Droogmakerij de Beemster (Beemster Polder)' has mentioned 'UNESCO World Heritage Site' in the following places:
Occurrence Sentence Text Source
Because of its historical relevance, and because the original structure of the area is still largely intact, the Beemster was inscribed on the UNESCO World Heritage Site list in 1999.
In addition in the Beemster Polder there are five fortresses as part of the Stelling van Amsterdam, another UNESCO World Heritage Site.