I guess these gates are from the time when this property was occupied by a church school. It looks across at Saint Marys church. The entire city block, on Church street, steep, with extensive views, changed and became residential these last 10 - 20 years. 
There, the former convent was in a large double story 'Victorian' style residence, with verandah, out houses, garden and large trees. Then convent was demolished and school closed up, a new building was tried to be swept away again for development.