Camp originally established on River Wye, say, for sport (7)
I believe the answer is:
archery
'for sport' is the definition.
(archery is a kind of sport)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for archery that I've seen before include "Bowman's sport" , "Target sport - Olympic event in from 1900-08, in 1920 and since 1972" , "The sport of bowmen" , "Bowmanship" , "Shooting with bows and arrows" .)