A roughly sub-rectangular enclosure, some 86 metres along its longer axis, sits to the south and south-east of a moated site complex at Thomastown Demesne, and much of what survives is legible only as low banks and shallow depressions in the grass. That kind of understatement is typical of field systems from this period: the infrastructure of everyday agricultural life, easily overlooked, rarely excavated, and all the more telling for it.

The boundaries of the enclosure are defined by a linear depression running along the west-south-west side and a slight bank to the south-south-east, which extends further in both directions before terminating, on one side at an existing field boundary and on the other at a large oval depression measuring roughly 15 metres by 9 metres. That oval hollow, and others like it nearby, may represent small quarried areas, places where stone or material was taken out of the ground for construction or repair. To the north-east, a curving bank of around 96 metres is thought to be a modified remnant of a levelled moated site, a type of medieval enclosure in which a raised platform, typically the site of a manorial residence or defended farmstead, was surrounded by a water-filled or wet ditch. The interior of the field system is generally level, though with some undulation in the northern half. Running east to west, a linear channel about 4.5 metres wide is cut by a second depression of similar dimensions; this channel may be connected to a leat system, that is, an artificial watercourse used to direct water for milling or drainage, or it may be the trace of an old trackway. The relationship between these features and the broader moated complex nearby suggests the field system was part of the same managed landscape, a working agricultural arrangement laid out in close proximity to whatever residence or centre of authority once occupied the higher ground.