▁h ik ers , ▁and ▁mountain ▁b ik ers . ▁Cl iff ▁C ave ▁can ▁be ▁accessed ▁from ▁this ▁trail . ▁The ▁trail ▁goes ▁up ▁a ▁valley , ▁then ▁reaches ▁a ▁kar st ▁plate au ▁and ▁forms ▁a ▁loop ▁in ▁the ▁wood lands . ▁The ▁fl ora ▁include ▁h ick ory ▁and ▁o ak ▁trees . ▁ ▁River ▁Bl uff ▁Tra il ▁ ▁The ▁River ▁Bl uff ▁Tra il ▁is ▁a ▁ 1 - mile ▁flat , ▁natural ▁t read way ▁trail ▁accessible ▁to ▁e quest ri ans , ▁h ik ers , ▁and ▁mountain ▁b ik ers . ▁This ▁trail ▁aff ords ▁a ▁scen ic ▁v antage ▁point ▁to ▁see ▁the ▁Mississippi ▁River ▁from ▁the ▁bl uff s . ▁Flora ▁include ▁pra irie ▁grass es ▁including ▁the ▁native ▁side - o ats ▁gr ama ▁and ▁little ▁bl uest em , ▁wild flow ers , ▁and ▁ch ink ap in ▁o ak ▁trees . ▁The ▁fa una ▁is ▁being ▁threatened ▁by ▁invas ive ▁species ▁such ▁as ▁h one ys uck le . ▁ ▁Inc idents ▁On ▁July ▁ 2 3 , ▁ 1 9 9 3 , ▁six ▁people ▁were ▁killed ▁while ▁expl oring ▁the ▁cave ▁due ▁to ▁a ▁flash ▁flo od . ▁Four ▁coun sel ors ▁and ▁ 1 2 ▁boys ▁from ▁the ▁St . ▁Joseph ' s ▁Home ▁for ▁Boys , ▁a ▁resident ial ▁treatment ▁center ▁for ▁ab used ▁or ▁trouble d ▁youth , ▁were ▁expl oring ▁the ▁area . ▁Seven ▁were ▁tra pped ▁in ▁the ▁cave ▁when ▁rain ▁caused ▁flash