Castle Field Camp/ Graig-llwyn
Castle Field Camp, also known by the associated estate name Graig-llwyn, is an Iron Age hillfort and enclosure situated on a prominent ridge in the southern reaches of the Caerphilly basin in south Wales. The coordinates place it in the vicinity of Lisvane and Llanishen, on the northern fringe of Cardiff, where ancient earthworks are occasionally encountered amid the suburban and semi-rural landscape. The site is one of several prehistoric enclosures that punctuate the ridgelines and upland fringes of this part of the Vale of Glamorgan and the Valleys transition zone, where Iron Age communities exploited elevated terrain for defensive and pastoral purposes. What makes Castle Field Camp particularly interesting in its local context is how it survives as a remnant of deep prehistory just a short distance from the expanding city of Cardiff, a juxtaposition that gives the site a quiet, almost secret character that casual visitors rarely encounter.
The earthworks at Castle Field Camp are believed to date broadly to the Iron Age, a period spanning roughly 800 BC to the Roman conquest of southern Wales in the first century AD. Like many hillforts and enclosures of this region, it likely served as a focal point for a small agricultural community, providing defensible space for livestock and people during times of threat, as well as functioning as a social and perhaps ritual centre. The Silures, the Iron Age tribe who dominated what is now south-east Wales and were famously resistant to Roman advances, inhabited this wider territory, and sites such as Castle Field Camp would have formed part of the dispersed network of enclosed settlements and farmsteads across the landscape. No dramatic historical events are specifically recorded here, but the earthworks themselves are the silent testament to sustained occupation and community life across many centuries.
In physical terms, the site consists of earthwork banks and ditches that define an enclosure on the ridge, though like many such sites in lowland and semi-lowland Wales, the remains are not dramatically upstanding and require some familiarity with the landscape to read clearly. Vegetation, scrub, and in places woodland growth have softened the original profiles. Standing at or near the site on a clear day, however, the logic of the location is immediately apparent: the ridge commands wide views southward toward Cardiff and the Bristol Channel, and the sense of elevation and openness would have made the position strategically valuable to its original inhabitants. The sounds are those of the surrounding countryside and distant suburban life — birdsong, wind through hedgerows, the occasional vehicle.
The surrounding area is a fascinating blend of the ancient and the modern. Graig-llwyn itself is associated with a wooded estate and the broader green corridor that runs along the ridge north of Llanishen and Lisvane, two communities now absorbed into north Cardiff. Lisvane Reservoir and the Llanishen Reservoir are nearby landscape features, and the area retains patches of semi-natural woodland and hedged farmland that give it a pleasantly rural character despite its proximity to the city. The Rhymney Valley corridor lies to the north-east, and the whole landscape sits at the margin between the more urbanised southern lowlands and the upland coalfield to the north. Several other prehistoric and medieval features are recorded within a few kilometres.
For visitors, access to the general area is via north Cardiff, with Lisvane and Llanishen both served by Cardiff's suburban rail network as well as bus routes. The site itself sits within private or semi-private land and does not have the infrastructure of a managed heritage attraction — there are no car parks, interpretation boards, or marked trails specifically for Castle Field Camp. Visiting therefore requires care regarding land access, and those wishing to see the earthworks should check current access arrangements, ideally consulting the Coflein database maintained by the Royal Commission on the Ancient and Historical Monuments of Wales (RCAHMW), which holds records for sites of this type. The best times to visit from a landscape perspective are late autumn and winter, when reduced vegetation makes earthworks more legible.
One of the quietly compelling aspects of sites like Castle Field Camp is how thoroughly they disappear from common knowledge while remaining physically present in the ground. Thousands of people live within a few kilometres of these earthworks and remain entirely unaware of them, yet they represent more than two millennia of separation from the people who built and used them. The dual name of the site — Castle Field Camp and Graig-llwyn — reflects the layered naming conventions of the Welsh landscape, where estate names, field names, and archaeological descriptors accumulate over time. Graig-llwyn translates loosely from Welsh as something akin to "rocky grove" or "ridge grove," a name that suits the wooded, elevated character of the location and points to the deep linguistic continuity of Welsh place-naming across the landscape.