42386
Historically , the tidal reaches of the Usk have been used as a major shipping port for much of the last millennium , mostly because of its wide and deep mouth , and good navigable access from the Severn Estuary and the Bristol Channel and thence access to home waters and further overseas .
 location: Usk; location: Severn Estuary; location: Bristol Channel
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Usk, Severn Estuary, Bristol Channel 
Answer:
 location: Usk; location: Severn Estuary; location: Bristol Channel