The enclosure at Middletown survives not as upstanding earthwork but as a cropmark, a phenomenon that occurs when buried features affect the growth of crops above them; a filled ditch retains more moisture than the surrounding soil, producing a narrow band of lusher, slightly taller growth that, from altitude, traces the outline of whatever once lay below. On Google Earth imagery captured in June 2018, that outline appeared as a positive cropmark, meaning the ditch showed up as a greener or more vigorous strip against the paler surrounding crop.

The enclosure is circular in plan, with an external diameter of approximately 42.5 metres and a ditch roughly two metres wide. No entrance gap is visible in the available evidence, which is itself quietly interesting; most enclosed settlements of this type preserve at least a hint of a causeway or break where people and livestock passed through. Whether that absence reflects the limits of cropmark resolution, later disturbance, or something about the original design of the site remains an open question. The enclosure sits about 725 metres west-south-west of a cluster of monuments in the neighbouring townland of Springhill, itself centred on a recorded enclosure, and an unnamed east-west stream, a tributary of the Mayne River, runs approximately 120 metres to the south. That proximity to water and to other monument types is a recurring pattern in Irish enclosed settlements, which range in date from the Bronze Age through to the early medieval period, though no dating evidence for this particular site is currently recorded.

Because the site lies within a working agricultural field and has no surface expression, there is little to see on the ground at any time of year. The cropmark is only legible from the air or via satellite imagery during dry summer conditions, when moisture stress in the crop makes buried features most apparent. Consulting the Google Earth historical imagery layer for the area around Middletown townland, filtering for late June coverage, is the most practical way to examine the enclosure. The nearby Springhill monument complex, which is separately recorded, may offer more context for understanding what this part of north Dublin looked like when this ditch was still an active boundary rather than a faint green circle glimpsed by a satellite passing overhead.