187808
The freeway heads in a generally northwest direction , with interchanges providing access to the nearby towns of Burlington , Bedford , Billerica , Carlisle , and Chelmsford .
 Burlington, Bedford, Billerica, Carlisle, Chelmsford
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Burlington, Bedford, Billerica, Carlisle, Chelmsford