▁H esse ▁High lands ; ▁river ▁lies ▁on ▁the ▁w ester ▁boundary ▁of ▁the ▁area ▁ ▁Ful da ▁- ▁mouth ▁lies ▁on ▁the ▁north western ▁border ; ▁left ▁trib ut aries ▁above ▁the ▁E der ▁lie ▁outside ; ▁of ▁the ▁catch ment ▁area ▁of ▁the ▁E der , ▁which ▁is ▁largely ▁in ▁the ▁Rest - F ul da ▁catch ment ▁area , ▁only ▁the ▁right - hand ▁trib ut aries ▁of ▁the ▁Schw alm ▁come ▁from ▁the ▁East ▁H esse ▁High lands , ▁whilst ▁the ▁E der ▁is ▁fed ▁by ▁the ▁West ▁H esse ▁High lands ▁apart ▁from ▁the ▁upper ▁course ▁which ▁is ▁fed ▁by ▁the ▁Sü der ▁U pl ands . ▁ ▁Stre u ▁- ▁lower ▁course ▁in ▁the ▁Gra bf eld ▁ ▁Br end ▁- ▁middle ▁and ▁lower ▁reaches ▁lie , ▁without ▁major ▁trib ut aries , ▁in ▁the ▁part ▁of ▁the ▁Süd rh ön ▁belonging ▁to ▁the ▁Sp ess art ▁region ▁ ▁S inn ▁- ▁middle ▁and ▁lower ▁courses ▁lie ▁in ▁various ▁parts ▁of ▁the ▁Sp ess art ▁ ▁Bra cht ▁and ▁Se emen bach ▁- ▁lower ▁courses ▁lie , ▁without ▁major ▁trib ut aries , ▁in ▁the ▁B üd ingen ▁Forest ▁region ▁of ▁the ▁Sp ess art ▁ ▁N id der ▁- ▁from ▁the ▁Se emen bach ▁on ▁the ▁it ▁runs ▁along ▁the ▁eastern ▁boundary ▁of ▁the ▁W etter au ▁to ▁the ▁R onne burg ▁Hills , ▁but ▁without ▁any ▁major ▁trib ut aries ▁ ▁Hor lo ff ▁- ▁middle ▁and ▁lower ▁reaches ▁on ▁the ▁sout he astern ▁boundary