What makes Keelhilla particularly arresting is not any single feature but the sheer density of different periods layered across one hillside: field walls, a possible burial ground, ancient cooking sites, and a holy well all occupying the same stretch of ground.

The field system is considered to be of multiperiod date, meaning it was not built or used in a single era but accumulated over successive generations of activity. Towards the south-west, a number of field walls form a fairly rectilinear pattern, apparently built in slab wall construction, where large flat stones are set upright or stacked to create boundaries rather than the dry-stone coursing more commonly associated with later agricultural enclosures. A possible burial ground lies at this same south-western end. Moving east, where the karst slope gives way to reclaimed pasture, the character of the site shifts again. Here there are two fulachtaí fia, the plural form of fulacht fia, which are the burnt mounds left behind by prehistoric cooking or industrial activity, typically identified by a distinctive spread of fire-cracked stones. Alongside them sits a holy well, a type of water source that in Ireland frequently carries pre-Christian associations but was often absorbed into Christian devotional practice over the centuries. The combination of prehistoric cooking monuments, a sacred water source, and field boundaries that may span multiple archaeological periods makes this a genuinely complex site. It was brought to the attention of the National Monuments Service by Ros Ó Maoldúin.