▁narrow ▁valley ▁to ▁a ▁point ▁just ▁beyond ▁Br ut on ▁where ▁it ▁is ▁joined ▁by ▁the ▁River ▁Pitt . ▁Here ▁it ▁takes ▁a ▁me and ering ▁route ▁through ▁a ▁broad , ▁flat - bottom ed ▁valley ▁between ▁Castle ▁C ary ▁and ▁Al ham pton . ▁By ▁the ▁time ▁it ▁reaches ▁Balt ons borough ▁it ▁is ▁only ▁some ▁ ▁above ▁sea ▁level ▁and ▁the ▁surrounding ▁coun tr ys ide ▁is ▁dra ined ▁into ▁it ▁by ▁way ▁of ▁numerous ▁rh yn es . ▁It ▁passes ▁G last on bury , ▁where ▁it ▁acts ▁as ▁a ▁natural ▁boundary ▁with ▁nearby ▁village ▁of ▁Street , ▁before ▁flow ing ▁in ▁a ▁largely ▁artificial ▁channel ▁across ▁the ▁Som erset ▁Level s ▁and ▁into ▁the ▁River ▁Par rett ▁at ▁Burn ham - on - Se a . ▁It ▁is ▁joined ▁by ▁the ▁North ▁D rain , ▁White ' s ▁River ▁( which ▁takes ▁the ▁water ▁of ▁the ▁River ▁She pp ey , ▁C ri pp s ▁River ▁( an ▁artificial ▁channel ▁that ▁connect s ▁it ▁to ▁the ▁River ▁H unt sp ill ) ▁and ▁many ▁d rain age ▁rh yn es ). ▁It ▁is ▁connect ▁to ▁the ▁River ▁A xe ▁through ▁several ▁of ▁these ▁channels ▁which ▁are ▁controlled ▁by ▁sl u ices . ▁It ▁is ▁tid al ▁below ▁the ▁sl u ices ▁at ▁New ▁C ly ce ▁Bridge ▁in ▁High bridge . ▁ ▁Bow ▁Bridge ▁is ▁a ▁ 1 5 th - century ▁Pack hor se ▁bridge ▁over ▁the ▁River ▁Br ue ▁in ▁P lo x , ▁Br ut on