pe v ine ▁cross ▁which , ▁according ▁to ▁tradition , ▁was ▁for ged ▁by ▁Saint ▁N ino , ▁a ▁C app ado cian ▁woman ▁who ▁pre ached ▁Christian ity ▁in ▁the ▁C au cas us ▁in ▁the ▁early ▁ 4 th ▁century . ▁King ▁V ak ht ang ▁III ▁gave ▁the ▁reli qu ary ▁itself ▁in ▁the ▁early ▁ 1 4 th ▁century . ▁ ▁The ▁S ioni ▁C athedral ▁was ▁where ▁the ▁Russian ▁Imperial ▁manif esto ▁on ▁the ▁an nex ation ▁of ▁Georgia ▁was ▁first ▁published . ▁On ▁April ▁ 1 2 , ▁ 1 8 0 2 ▁the ▁Russian ▁commander - in - ch ief ▁in ▁Georgia , ▁General ▁Karl ▁von ▁Kn or ring , ▁assemble d ▁the ▁Georg ian ▁nobles ▁in ▁the ▁C athedral , ▁which ▁was ▁then ▁surrounded ▁by ▁Russian ▁troops . ▁The ▁nobles ▁were ▁forced ▁to ▁take ▁an ▁o ath ▁to ▁the ▁Russian ▁Imperial ▁crown ; ▁any ▁who ▁disag re ed ▁were ▁taken ▁into ▁cust ody . ▁ ▁S ioni ▁C athedral ▁remained ▁functional ▁through ▁Soviet ▁times , ▁and ▁was ▁partially ▁renov ated ▁between ▁ 1 9 8 0 ▁and ▁ 1 9 8 3 . ▁ ▁Architecture ▁ ▁The ▁S ioni ▁C athedral ▁is ▁a ▁typical ▁example ▁of ▁medieval ▁Georg ian ▁church ▁architecture ▁of ▁an ▁ins cribed ▁cross - in - square ▁design ▁with ▁project ing ▁pol yg onal ▁a ps es ▁in ▁the ▁east ▁fa ç ade . ▁Main ▁entrance ▁is ▁in ▁the ▁west ▁side . ▁The ▁d ome ▁with ▁the ▁th ol ob ate ▁is