West Ardougne

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West Ardougne is the western half of Ardougne, separated with a wall because of a plague. This is the location of several Quests, including:

Plague City Biohazard Underground Pass

You cannot enter the city until you start Plague City, but even then it doesn't contain much. However, it is the entrance to the Underground Pass, which leads to the Elf Land of Tirannwn.