The church is on an island at the junction of Park Avenue and St Johns Road, which continues east towards the sea at Sandymount Strand.

Park Avenue of Sandymount, like its famous namesake in New York City, is noted for its high property prices and wealthy residents.

[4] Park Avenue runs through an area which was, in former times, known as The Marsh, being a 13-acre (53,000 m2) pond or lough in the estuary of the River Liffey.

[7] The Sisters of Mercy had a convent, orphanage and school on Park Avenue which was founded in 1856 and reference to their activities is made in the novel Ulysses.

[8][9] When high property prices made sales of their grounds attractive, this posed a dilemma for the religious order but 3.15 acres (12,700 m2) were sold for the construction of 78 houses in high-density development.