mount ed ▁by ▁a ▁crown . ▁On ▁top ▁of ▁the ▁ped iment ▁stands ▁a ▁de er ▁head ▁with ▁a ▁cross ▁between ▁the ▁ant lers ▁( done ▁by ▁the ▁sculpt or ▁Paolo ▁Mor elli ▁(† ▁ 1 7 1 9 ), ▁in ▁reference ▁to ▁the ▁legend ▁of ▁Saint ▁E ust ace . ▁ ▁An ▁iron ▁gate , ▁made ▁by ▁Gian ▁Batt ista ▁Cont ini , ▁clos es ▁off ▁the ▁por ch . ▁ ▁The ▁square ▁Roman es que ▁camp an ile ▁is ▁situated ▁on ▁the ▁back ▁of ▁the ▁church ▁at ▁its ▁left ▁side . ▁Const ruction ▁was ▁started ▁in ▁ 1 1 9 6 ▁under ▁the ▁pont ificate ▁of ▁Pope ▁Cel est ine ▁III . ▁The ▁top ▁part ▁can ▁be ▁dated ▁back ▁to ▁the ▁end ▁of ▁the ▁ 1 2 th ▁century , ▁while ▁the ▁base ▁is ▁somewhat ▁older ▁and ▁can ▁be ▁dated ▁at ▁ca . ▁ 1 0 9 0 . ▁ ▁Inter ior ▁The ▁interior ▁has ▁a ▁cru c iform ▁architect ural ▁plan ▁and ▁consists ▁of ▁a ▁single ▁nave . ▁Its ▁construction ▁was ▁carried ▁out ▁in ▁m ature ▁Bar o que ▁style ▁under ▁the ▁super vision ▁of ▁the ▁architect s ▁Ces are ▁Cor var a ▁and ▁Antonio ▁C ane vari . ▁The ▁nave ▁is ▁marked ▁on ▁each ▁side ▁by ▁three ▁pil aster s ▁rest ing ▁on ▁a ▁broad ▁base . ▁The ▁pil aster s ▁are ▁deck ed ▁with ▁fl uted ▁white ▁mar ble ▁and ▁sur mount ed ▁by ▁composite ▁capit als . ▁ ▁The ▁rib ▁v ault ▁is ▁st u cco ed