, ▁the ▁cave ' s ▁Upper ▁Pale ol ith ic ▁layers ▁contain ▁a ▁sequence ▁of ▁Aur ign aci an , ▁Gra v ett ian ▁and ▁Mag d alen ian ▁artifact s . ▁In ▁ 1 9 5 6 ▁the ▁first ▁human ▁foss ils ▁were ▁discovered ▁within ▁a ▁fire place ▁in ▁the ▁center ▁of ▁the ▁cave , ▁a ▁discovery ▁which ▁made ▁important ▁contributions ▁to ▁the ▁found ational ▁understanding ▁of ▁the ▁Mag d alen ian ▁culture ▁of ▁central ▁Europe . ▁ ▁Site ▁ ▁Br ill en hö h le ▁is ▁located ▁in ▁the ▁Ach ▁Valley , ▁lying ▁about ▁ ▁above ▁the ▁Ach ▁River ▁below . ▁The ▁site ▁der ives ▁its ▁name ▁from ▁the ▁two ▁holes ▁in ▁the ▁cave ' s ▁ce iling , ▁which ▁together ▁res emble ▁a ▁pair ▁of ▁spect acles . ▁The ▁cave ▁is ▁essentially ▁a ▁single ▁room ▁with ▁a ▁diameter ▁of ▁, ▁an ▁average ▁height ▁of ▁ ▁and ▁a ▁length ▁of ▁. ▁A ▁small ▁side ▁cave ▁of ▁ ▁width ▁and ▁ ▁height , ▁called ▁V es pers hö h le ▁runs ▁from ▁the ▁entrance ▁around ▁ ▁towards ▁the ▁east . ▁As ▁the ▁site ▁is ▁in ▁an ▁advanced ▁state ▁of ▁decay , ▁it ▁has ▁been ▁designated ▁a ▁cave ▁ru in . ▁However , ▁the ▁open ings ▁in ▁the ▁roof ▁allow ▁smoke ▁to ▁escape ▁and ▁sufficient ▁light ▁to ▁enter , ▁while ▁still ▁being ▁small ▁enough ▁to ▁keep ▁the ▁cave ▁mostly ▁dry ▁during ▁periods ▁of ▁ra inf all . ▁Rec urrent ▁pre histor ic ▁human ▁occupation ▁at ▁the ▁site ▁indicates ▁that ▁conditions ▁at ▁the ▁cave