▁Bas in , ▁sub g la cial ▁bas in ▁in ▁Ant arct ica <0x0A> </s> ▁The ▁D ja ▁River ▁( also ▁known ▁as ▁the ▁Ng oko ▁River ) ▁is ▁a ▁stream ▁in ▁west - central ▁Africa . ▁It ▁forms ▁part ▁of ▁Cam ero on – Rep ublic ▁of ▁Congo ▁border ▁and ▁has ▁a ▁course ▁of ▁roughly ▁. ▁ ▁R ising ▁sout heast ▁of ▁the ▁sout he astern ▁Cam ero on ▁town ▁of ▁Ab ong - M b ang , ▁the ▁D ja ▁Fa unal ▁Reserve , ▁which ▁was ▁named ▁a ▁UN ES CO ▁World ▁Heritage ▁Site ▁in ▁ 1 9 8 7 , ▁lies ▁along ▁the ▁banks ▁of ▁its ▁upper ▁course . ▁It ▁protect s ▁one ▁of ▁the ▁largest ▁tract s ▁of ▁tropical ▁rain for est ▁in ▁Africa . ▁Form ing ▁its ▁natural ▁boundary , ▁and ▁almost ▁completely ▁enc ir cling ▁the ▁reserve ▁( except ▁to ▁the ▁south - west ), ▁cl iffs ▁run ▁along ▁the ▁course ▁of ▁the ▁river ▁in ▁the ▁south ▁part ▁of ▁the ▁reserve ▁for ▁ 6 0   km ▁and ▁are ▁associated ▁with ▁a ▁section ▁of ▁the ▁river ▁which ▁is ▁broken ▁by ▁rap ids ▁and ▁water falls . ▁Following ▁its ▁course ▁in ▁the ▁reserve , ▁the ▁D ja ▁flows ▁approximately ▁sout heast ▁past ▁Mol ound ou , ▁below ▁which ▁small ▁boats ▁can ▁navigate . ▁At ▁O u esso , ▁in ▁the ▁Republic ▁of ▁Congo , ▁it ▁em pt ies ▁into ▁the ▁Sang ha ▁River . ▁ ▁Every ▁year , ▁po ach ers ▁travel ▁up ▁the ▁D ja ▁for ▁central