Perched on the western edge of Kill Hill in County Kildare, this ancient hillfort commands sweeping views across the tillage fields and pastures towards Naas. The site occupies a gentle, domed summit that rises between 120 and 153 metres above sea level, positioned at the northeastern foothills of the Wicklow Mountains. What makes this hillfort particularly impressive is its sheer scale; covering over 26 hectares, it ranks among Ireland’s largest hillforts, with its outermost defences measuring nearly 600 metres in diameter.

The monument consists of three concentric earthen banks, now topped with modern hedgerows, that follow the natural contours of the hill. These defensive rings are widely spaced, averaging about 120 metres apart, creating a series of terraced enclosures that would have provided multiple lines of defence for the ancient inhabitants. The outer ring remains largely intact and complete, whilst the middle and inner enclosures have suffered from centuries of agricultural activity. Much of the inner defences can now only be seen from the air, appearing as crop marks in aerial photographs, though they’re invisible to visitors walking the site today due to heavy vegetation and later field boundaries.

Archaeological investigation of the site has been limited, but it was thoroughly documented in the Atlas of Hillforts of Britain and Ireland using LiDAR technology. The hillfort appears on both the first and second edition Ordnance Survey maps, initially recorded as a series of curving field boundaries before its true significance was recognised. A small ring barrow lies tucked between the inner and middle enclosures on the eastern side, hinting at the site’s long history of human occupation. Today, the interior serves as pasture land, with sections of the western area given over to scrubland, whilst the ancient boundaries continue to define modern townland divisions between Kill Hill, Boherphilip, and Rathgorragh.