As farms gave way to residential housing, the Vanderbilt family built homes in the area, including two which still stand at the corner of Victory Boulevard and Clove Road.

Sunnyside was once the home of a campus of the College of Staten Island, located at the foot of Emerson Hill.

Sunnyside Hospital was located on Little Clove Road and Ontario Avenue, but was demolished in the 1960s to make way for the Staten Island Expressway (I-278).

A large percentage of Sunnyside's residents are civil service workers, this demographic trait being typical of many Mid-Island neighborhoods.

Slosson Avenue forms an unofficial western boundary, separating Sunnyside from Castleton Corners.