▁ 1 5 5 6 ▁it ▁was ▁occupied ▁by ▁Spanish ▁soldiers . ▁During ▁the ▁Roman ▁Republic , ▁it ▁remained ▁loyal ▁to ▁the ▁Pope . ▁During ▁the ▁Napole onic ▁occupation ▁( 1 8 0 9 – 1 8 1 4 ) ▁numerous ▁members ▁of ▁the ▁pap al ▁administration , ▁as ▁well ▁as ▁bishop ▁Giuseppe ▁della ▁Casa , ▁were ▁deport ed ▁to ▁France . ▁It ▁became ▁part ▁of ▁Italy ▁in ▁ 1 8 7 0 . ▁ ▁During ▁World ▁War ▁II ▁it ▁suffered ▁heavy ▁destru ctions ▁and ▁human ▁vict ims . ▁ ▁Main ▁s ights ▁ ▁An cient ▁remains ▁Al atri ▁has ▁well - pres erved ▁fort ifications ▁constructed ▁of ▁t etra hed ral ▁and ▁pol yg onal ▁blocks ▁of ▁local ▁lim estone ▁well ▁joint ed . ▁It ▁is ▁almost ▁entirely ▁an ▁emb ank ing ▁wall , ▁as ▁is ▁the ▁rule ▁in ▁the ▁cities ▁of ▁this ▁part ▁of ▁Italy , ▁with ▁a ▁maximum ▁height , ▁probably , ▁of ▁about ▁. ▁Two ▁of ▁the ▁gates ▁( of ▁the ▁perhaps ▁five ▁once ▁existing ) ▁are ▁still ▁to ▁some ▁extent ▁preserved , ▁and ▁three ▁post ern s ▁are ▁to ▁be ▁found . ▁ ▁In ▁the ▁centre ▁of ▁the ▁city ▁r ises ▁a ▁hill ▁which ▁was ▁adopted ▁as ▁the ▁cit adel . ▁Rem ains ▁of ▁the ▁fort ifications ▁of ▁three ▁success ive ▁periods ▁can ▁be ▁trac ed , ▁of ▁which ▁the ▁last , ▁perhaps ▁a ▁little ▁more ▁recent ▁than ▁that ▁of ▁the ▁city ▁wall , ▁is ▁the ▁best ▁preserved . ▁In ▁the ▁first ▁two ▁periods ▁the ▁construction ▁is ▁rough