sequently ▁he ▁and ▁Chris ▁Jew ell ▁connected ▁the ▁newly ▁established ▁Mon ast ir ▁S ink ▁– ▁Upper ▁C rad le ▁system , ▁extending ▁the ▁Mar ble ▁Arch ▁system ▁to ▁. ▁The ▁discover ies ▁make ▁this ▁the ▁longest ▁cave ▁in ▁Northern ▁Ireland . ▁ ▁H ydro log y ▁and ▁development ▁ ▁The ▁Mar ble ▁Arch ▁C ave ▁system ▁is ▁chief ly ▁formed ▁from ▁three ▁rivers ▁which ▁d rain ▁off ▁the ▁Mar l bank ▁area ▁on ▁the ▁north ▁side ▁of ▁Cu il c agh ▁mountain . ▁From ▁west ▁to ▁east , ▁these ▁trib ut aries ▁are ▁the ▁S ru h ▁Cro ppa , ▁the ▁Ag hin ra wn ▁( or ▁Mon ast ir ) ▁and ▁the ▁O wen bre an . ▁ ▁The ▁Pro d ' s ▁Pot ▁– ▁C asc ades ▁R ising ▁section ▁of ▁the ▁system ▁( connected ▁to ▁Mar ble ▁Arch ▁C aves ▁in ▁ 2 0 0 9 ) ▁has ▁a ▁complex ▁hydro log y ▁which ▁includes ▁d rain age ▁from ▁at ▁least ▁five ▁small ▁s inks ▁on ▁the ▁eastern ▁Mar l bank ▁( G ort ma conn ell ▁Pot , ▁Little ▁G ort ma conn ell ▁Pot , ▁Sm o key ▁Mountain ▁S ink ▁and ▁two ▁un named ▁s inks ▁at ▁Brook field ▁have ▁been ▁d ye ▁trac ed ▁to ▁C asc ades ); ▁sections ▁of ▁the ▁O wen bre an ▁River ▁up stream ▁of ▁its ▁main ▁sink ▁at ▁Pol las um era ; ▁and ▁most ▁not ably ▁Go at ▁Pot , ▁Ag hat ir our ke ▁Pot , ▁P