381341
The arboretum has twelve miles ( 19 km ) of trails ( two of which are suitable for wheelchairs ) , a visitor center , an indoor classroom with seating for 40 people , a picnic shelter and a meadow .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 None