13703
To the southeast , the upper reaches of the Thames Valley and towns such as Lechlade , Tetbury and Fairford are often considered to mark the limit of this region .
 Thames Valley, Lechlade, Tetbury, Fairford
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Thames Valley, Lechlade, Tetbury, Fairford