2460
Sometimes gatehouses formed part of town fortifications , perhaps defending the passage of a bridge across a river or a moat , as Monnow Bridge in Monmouth .
 location: Monmouth
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: Monmouth