The site's history stretches back to at least 1640, when Anne Hussy, noted in records as an Irish Catholic, held 338 acres here. The Civil Survey of 1654 paints a picture of a working estate complete with a stone house, an old castle, and ten cabins; clear evidence of a thriving rural community. The Hussy family's influence extended beyond Moynalvy itself, with Anne owning an additional 60 acres in nearby Crickstown and other family members holding lands throughout the barony of Deece.

Aerial photographs from the 1970s reveal the fascinating remnants of an ancient field system that once organised this landscape. Covering approximately 25.5 hectares across nine fields, a network of earthwork banks and ditches creates a patchwork of small rectangular and irregular plots, each measuring roughly 60 by 50 metres. These banks, typically three metres wide and standing between 20 and 80 centimetres high, accompanied by ditches of similar width, represent generations of farming and land management that shaped the countryside long before modern agriculture.

At the heart of these earthworks lies what may be a moated site; a raised rectangular platform measuring about 30 by 21 metres, defined by substantial earthen banks. Though erosion has softened its profile over the centuries, the banks remain impressive, particularly on the southeast side where they rise nearly a metre in height externally. Such moated sites were typically associated with medieval manor houses or fortified farmsteads, suggesting this was once the administrative or defensive centre of the estate, perhaps connected to the old castle mentioned in the 1654 survey.