CE , ▁developed ▁around ▁the ▁Nur ag he . ▁They ▁are ▁considered ▁by ▁sch ol ars ▁the ▁most ▁impress ive ▁expression ▁of ▁the ▁Nur ag ic ▁civil ization ▁and ▁were ▁included ▁in ▁the ▁UN ES CO ▁list ▁of ▁World ▁Heritage ▁S ites ▁in ▁ 1 9 9 7 ▁as ▁Su ▁Nur axi ▁di ▁Bar um ini . ▁ ▁Nur ag he ▁ ▁Str ucture ▁ ▁The ▁oldest ▁part ▁of ▁the ▁Nur ag he ▁consists ▁of ▁a ▁central ▁tower ▁with ▁three ▁super posed ▁ch amb ers ▁( 1 8 . 6 m ▁high ). ▁It ▁was ▁built ▁in ▁blocks ▁of ▁bas alt ▁between ▁the ▁sevent e enth ▁and ▁th ir teenth ▁centuries ▁B CE . ▁Later , ▁during ▁the ▁Late ▁Bron ze ▁Age , ▁four ▁to wers ▁joined ▁by ▁a ▁cur tain ▁wall ▁with ▁an ▁upper ▁bal con y ▁( no ▁longer ▁ext ant ) ▁were ▁built ▁around ▁the ▁central ▁tower , ▁all ▁communic ating ▁with ▁an ▁inner ▁cour ty ard ▁served ▁by ▁a ▁well . ▁During ▁the ▁Iron ▁Age , ▁the ▁complex ▁was ▁surrounded ▁by ▁a ▁cur tain ▁wall ▁with ▁seven ▁lo bes ▁( he pt al ob ate ). ▁ ▁Function ▁The ▁real ▁function ▁of ▁the ▁nur ag he ▁is ▁still ▁deb ated . ▁The ▁discover er ▁of ▁Su ▁Nur axi , ▁the ▁arch ae ologist ▁Giovanni ▁L ill iu , ▁confirmed ▁the ▁traditional ▁interpretation ▁of ▁for tr ess - site . ▁Other ▁arch ae olog ists ▁believe ▁that ▁the ▁oldest ▁part ▁of ▁the ▁complex ▁was ▁dest ined ▁for ▁a ▁religious ▁purpose