▁- ▁it ▁might ▁simply ▁have ▁been ▁holes ▁d ug ▁to ▁gain ▁construction ▁materials . ▁The ▁wall ▁also ▁was ▁built ▁in ▁p f ost ensch l itz ▁style , ▁pier ced ▁in ▁only ▁three ▁places ▁by ▁Z ang ent ore . ▁The ▁connecting ▁wall ▁following ▁the ▁southern ▁bank ▁of ▁the ▁Alt m ühl ▁was ▁added ▁only ▁in ▁the ▁last , ▁the ▁third , ▁stage ▁of ▁construction . ▁ ▁The ▁inner ▁r amp art , ▁also ▁connected ▁the ▁cl iffs ▁over looking ▁the ▁Dan ube ▁to ▁the ▁Alt m ühl . ▁It ▁is ▁ 9 3 0 ▁m ▁long ▁and ▁ext ant ▁to ▁a ▁height ▁of ▁up ▁to ▁ 4 ▁m . ▁On ▁its ▁outer ▁side ▁is ▁a ▁mo at ▁( 2 ▁m ▁deep , ▁ 7 ▁m ▁wide ) ▁and ▁a ▁b erm ▁( 5 ▁m ). ▁Two ▁Z ang ent ore ▁gave ▁access ▁to ▁the ▁Mich els berg . ▁In ▁construction ▁the ▁inner ▁r amp art ▁res emble d ▁the ▁outer ▁one . ▁It ▁was ▁completely ▁re built ▁once . ▁ ▁Al ong ▁the ▁southern ▁bank ▁of ▁the ▁Alt m ühl ▁a ▁ 3 . 3   km ▁long ▁wall ▁was ▁added ▁during ▁the ▁latest ▁period ▁of ▁construction . ▁This ▁was ▁the ▁structure ▁that ▁was ▁destroyed ▁by ▁canal ▁construction ▁in ▁the ▁nin ete enth ▁century . ▁Ex c av ations ▁un cover ed ▁evidence ▁of ▁one ▁gate ▁( added ▁later ), ▁however , ▁and ▁this ▁wall ▁had ▁been ▁of ▁the ▁p f ost ensch l itz - type . ▁The ▁wall ▁likely ▁cur