amb les ▁for ▁the ▁protection ▁of ▁storage ▁places ▁( including ▁c aves ), ▁fort ified ▁resid ences , ▁houses , ▁est ates ▁and ▁settlement s ▁from ▁attack ▁by ▁pred ators ▁or ▁enemies . ▁This ▁is ▁common ▁even ▁today ▁amongst ▁nom adic ▁tribes . ▁Julius ▁Ca esar ▁tells ▁e . g . ▁of ▁thick ▁H agen ▁which ▁were ▁laid ▁out ▁by ▁the ▁N er vi i , ▁one ▁of ▁the ▁most ▁powerful ▁Belg ic ▁tribes : ▁ ▁A ▁more ▁complicated ▁form ▁of ▁defence ▁was ▁the ▁classic ▁d itch ▁and ▁r amp art ▁system . ▁In ▁A . D . ▁ 1 6 , ▁T ac it us ▁reported ▁a ▁border ▁fort ification ▁built ▁by ▁the ▁Ang riv ari i , ▁the ▁Ang riv arian ▁Wall , ▁which ▁was ▁ere cted ▁to ▁defend ▁them ▁against ▁the ▁Cher us ci . ▁A ▁great ▁battle ▁was ▁fought ▁there ▁in ▁ 1 6 ▁AD . ▁The ▁most ▁important ▁border ▁fort ifications ▁were ▁said ▁to ▁have ▁been ▁at ▁Re h burg - Loc c um . ▁ ▁The ▁Ang lo - S ax on ▁Chron icle ▁speak s ▁of ▁a ▁B eb ban burg ▁around ▁A . D . ▁ 5 4 7 , ▁which ▁was ▁" first ▁fort ified ▁by ▁a ▁h edge ". ▁The ▁capit ular ies ▁of ▁Char lemagne ▁also ▁mention ▁" r amp arts ▁plant ed ▁with ▁h ed ges ". ▁ ▁In ▁England , ▁similar ▁fort ifications ▁are ▁called ▁" dy kes " ▁or ▁d itch es . ▁For ▁example , ▁B oker ley