1889
The Brocken plateau and other peaks near the border were part of a large military out-of-bounds area , which demonstrating walkers first entered on 3 December 1989 .
 location: Brocken
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 location: Brocken