At Killeen, atop a low rock outcrop surrounded by wet, poorly drained grassland, a medieval castle sits at the centre of an oval-shaped enclosure, and the ground around it still holds the faint geometry of a world that simply stopped. The bogland presses in from the west, dry land opens out to the north, south, and east, and a stream runs between the castle and the bog. Nothing here has been ploughed flat or tidied away.

Aerial photographs taken in 1966 as part of the Cambridge University Collection of Aerial Photography revealed the site in unusual clarity, showing the castle positioned within its enclosure and linear earthworks running up towards it from the east. On the ground, those earthworks are harder to read. Some of the ridges and depressions in the field to the east of the castle may relate to drainage, the ordinary business of managing wet ground, but others are thought to be settlement earthworks, the physical remains of whatever community once gathered around the castle. A medieval enclosure of this oval form often functioned as a bawn, essentially a walled or embanked courtyard associated with a defended residence, and the earthworks leading into it from the east suggest some kind of organised approach or former boundary. Because the field has remained unimproved, those features survive in at least partial form, slowly being read and debated rather than simply lost.