The monument includes a medieval moated site and associated pond situated at the northern end of Denham village, approximately 300m ENE of St John the Baptist's Church. The moat, which contains water and is for the most part from 7m to 13m in width, surrounds the north, east and south sides and the south western corner of a quadrangular central island with internal dimensions of approximately 65m WNW-ESE by 40m. A map made in 1757 shows that the moat originally extended around the western end of the island and although this western arm has been infilled, it will survive as a buried feature. A causeway across the southern arm is a modern feature, and the section of the moat around the corner to the west of this appears, on the evidence of the 18th century map and a later map of 1838, to have been enlarged internally since the mid-19th century to a width of up to 15m. College farmhouse, which stands towards the western end of the central island and is of uncertain date, is excluded from the scheduling, although the ground beneath it is included.
Approximately 20m to the west of the line of the western arm of the moat and parallel to it there is a linear pond about 73m long and between 7m and 10m wide, thought to be associated with the moat. The map of 1838 shows that the northern end of the pond originally extended eastwards towards the north west corner of the moat, enclosing the northern end of the area between. The pond is partially divided into two sections by a low ridge which projects from the eastern side approximately 55m from the northern end and opposite the south western corner of the moat. It is possible that the pond originated as two fishponds aligned end to end and connected by a sluice.
The moated site and the house it contained were among the possessions of Sir Henry Bedingfield which were seized by Parliament following the Civil War and the beheading of Charles I in 1649. A survey made in 1651 refers to it as one of two capital messuages (principal dwellings) in Denham and describes the house as the `mansion, commonly called Denham College, alias Denham Dungeon', although the house was `old, small and fit only to accommodate one tenant'. The house, built of timber, included a parlour, a hall, a kitchen or buttery, a cellar, a brewhouse, a bakehouse and one other small room, with six chambers on the upper floor, two dairies with a chamber over and a garret above that, and a small courtyard and garden within the moat. The reference to it as a capital messuage, together with its location close to the church and the village, suggest that it may at one time have been the site of a manor house, although by the 17th century the manor was located at Denham Hall, another moated site about 1.6km to the south west, close to the parish boundary. The name indicates a possible association with a college of secular clergy, and it has been suggested that such a college might have been founded here in the late 15th or early 16th century to serve the parish church.
The College farmhouse, all outbuildings, garden walls, inspection chambers, modern paving and the surfaces of modern trackways and paths, clothes line posts and all modern fences and gates are excluded from the scheduling, although the ground beneath these features is included.