Our Lady of Mercy parish is located at 500 South Oyster Bay Road, Hicksville NY 11801, telephone 516-931-4351. The parish website is linked here. The location is in northeast Hicksville, about a mile south of Exit 36 of the Northern State Parkway. The parish buildings are on the west side of South Oyster Bay Road, and across the street is Plainview.
The upper church, which is bright, seems to be locked on weekdays, except for funerals.
Looking north, the above photo shows the elementary school and church. This is not a business district, and the parish is surrounded by single-family homes.
The mailing address of the school is 520 South Oyster Bay Road, Hicksville NY 11801, telephone 516-433-7040. The school's website is linked here.