The Old Deer Park at Poyntstown is one of those features that reads as agricultural landscape until you start to measure it: 875 metres on its longer axis, 630 metres across, the whole thing oriented on a north-west-facing slope with open views across the lowlands to the west and north.

Deer parks were a feature of medieval and early modern lordship across Ireland and Britain, walled or embanked enclosures where deer were kept as a controlled resource for hunting and for the table, their maintenance a signal of wealth and authority. The Poyntstown example sits between two castle sites: Poyntstown castle lies about 250 metres to the west, accompanied by a seventeenth-century house, while Mellisson castle stands roughly 310 metres to the north-east. Either could plausibly have been the seat of whoever commissioned the enclosure, and it is not clear which castle the park originally served. The limestone wall on the southern and eastern sides still does practical work of a different kind, forming the townland boundary between Poyntstown and Mellisson. A map drawn up in 1824 already labels the area as a deer park, and the designation appears again on the Ordnance Survey six-inch map of 1840, suggesting it had been a recognised feature of the landscape long before either cartographic record was made.

The interior is mostly open grassland, running from flat ground at the north-western end up onto the lower slopes of the Slieveardagh hills at the south-eastern corner, where a single field has been planted with coniferous trees. The wall itself, roughly coursed limestone, survives well enough to follow on the ground, and its scale gives a clearer sense than most documentary sources could of what it meant to set aside this much land for a single, largely ceremonial purpose.