Description from record TQ 75 NW 4:
[Name centred TQ 74825973] Cossington [GT] (Remains of) (1) Cosington was an eminent manor. When it was visited by the author in 1776 it was a farmhouse with a plastered front, and had only been part of the ancient building. Debris and foundations were visible behind the house. Amongst these, the foundations of a stone building, 4 feet high, have been thought to be the remains of a free chapel, dedicated to St. Michael, founded temp Edward I by Sir Stephen de Cosenton, on account of its E W orientation. The author, however, thought that the chapel might have stood at a small distance from the house more under the brow of the hill. Not the least vestige remains to point it out. (2) Chapel mentioned 1444, dedicated to St. Michael. (3) Chapel of St Michael at Cosington founded in the reign of Edward I, 1272-1307, mentioned 1285. (4) "The author and a friend saw distinct traces of there having been a manor house and a chapel here this year". (5) Some remains still exist. (6) Remains consist of one broken wall, c.20 feet high and 10 feet wide. (7) TQ 74765975 At the north-east corner of a walled-in garden, are incorporated the remains of the west end of a domestic building The greater part of a chinmey stack some 7.0m high remains, with the moulded stone jamb of a window to the south of it set in the south wall. The walls are composed of stone with some tile, and patches of brick. The garden wall is of brick in English Bond, some 4.0m high. To the east of the site, the sloping ground has been cut back into a small rectangular terrace, and south of this a pond has been constructed by cutting back into the hill, the spoil employed in building a retaining bank of some size along the lower west side. These features may be contemporary with the site, but are probably quite late. GP/AO/59/6/3 from east. Antiquity Model survey correct. (8) Checked and correct. (9)

The following text is from the original listed building designation:
AYLESFORD CP PRATLING STREET TQ 75 NW (east side) 8/77 Ruins of Great Cossington - at Cossington Farm
- II
Manor house, now ruin. South, east and north walls and remains of west wall at north-west corner. Probably C16 early C17. Galletted random rubble plinth, very deep to north-east. Red brick with some blue brick above; some random rubble patching. All brick in English bond. 4 bee-boles on north wall facing south. Remains of large random rubble chimney-breast at north end of east wall, facing outwards (to east). There is a brass of John Cosyngton (d.1426) in Aylesford Church.
Listing NGR: TQ7432459781 (13)

<1> OS 6" 1936-47 (OS Card Reference). SKE48342.

<2> Custumale Roffense 1788 66 ff (J Thorpe) (OS Card Reference). SKE39532.

<3> Bygone Kent 1892 79 (Stead) (OS Card Reference). SKE38445.

<4> Arch Cant 29 1911 220 (Hussey) (OS Card Reference). SKE34939.

<5> Memorials of Malling 1892 29 (Fielding) (OS Card Reference). SKE46876.

<6> Rambles around Churches 1929 4 188 (Smetham) (OS Card Reference). SKE48962.

<7> SS 6" (M Roberts Rev 6.11.54) (OS Card Reference). SKE49534.

<8> F1 ASP 14-MAY-59 (OS Card Reference). SKE42103.

<9> F2 ASP 26-FEB-64 (OS Card Reference). SKE43172.

<10> DOE (HHR) Dist of Tonbridge and Malling Kent 1987 27 (OS Card Reference). SKE40403.

<11> Field report for monument TQ 75 NW 4 - May, 1959 (Bibliographic reference). SKE3847.

<12> Field report for monument TQ 75 NW 4 - February, 1964 (Bibliographic reference). SKE3848.

<13> English Heritage, List of Buildings of Special Architectural or Historic Interest (Map). SKE16160.