Ancient Monuments

History on the Ground

This site is entirely user-supported. See how you can help.

Castle Hills Wood ringwork and baileys

A Scheduled Monument in Thonock, Lincolnshire

We don't have any photos of this monument yet. Why don't you be the first to send us one?

Upload Photo »

Approximate Location Map
Large Map »

If Google Street View is available, the image is from the best available vantage point looking, if possible, towards the location of the monument. Where it is not available, the satellite view is shown instead.


Latitude: 53.414 / 53°24'50"N

Longitude: -0.7703 / 0°46'13"W

OS Eastings: 481831.743498

OS Northings: 391500.356889

OS Grid: SK818915

Mapcode National: GBR RX2Y.1X

Mapcode Global: WHFFZ.4GG4

Entry Name: Castle Hills Wood ringwork and baileys

Scheduled Date: 4 October 1932

Last Amended: 27 September 1999

Source: Historic England

Source ID: 1016970

English Heritage Legacy ID: 31639

County: Lincolnshire

Civil Parish: Thonock

Built-Up Area: Gainsborough

Traditional County: Lincolnshire

Lieutenancy Area (Ceremonial County): Lincolnshire

Church of England Parish: Gainsborough All Saints

Church of England Diocese: Lincoln


The monument includes the medieval ringwork and baileys known as Castle Hills.
Located in Castle Hills Wood on a west-facing escarpment overlooking the Trent
valley, it is thought to date from the late 11th or mid-12th century. In 1086
Thonock was held by Roger of Poitou and around 1115 by the Count of Mortain.
The site, which was referred to as the `castle of Gainsborough', was granted
by King Stephen to William de Roumare, Earl of Lincoln by 1146. In the late
12th and 13th centuries it became an important residence, notably of Edmund
Earl of Cornwall, brother of Edward I, and was the centre of a barony. The
site remained in residential use into the 15th century and the manor remained
a holding of the Duchy of Lancaster until 1563, by which time it had been

The monument takes the form of a ringwork with banked and ditched baileys
adjoining it to the north and south and a steep scarp to the west. The central
area of the ringwork is roughly circular in plan, measuring approximately 20m
in diameter, and includes a hollow thought to represent the location of buried
building remains such as a hall. The central area is enclosed by a bank and
external ditch. The bank measures up to 10m in width and is more pronounced on
the southern side of the central area. The ditch is steep-sided, measuring 15m
in width, and is also more pronounced on the southern side of the ringwork.
Additional defence was provided by another steep sided ditch, up to 5m deep,
embanked on both sides, which encloses the southern half of the ringwork.

The northern side of the ringwork is enclosed by a bailey believed to be
contemporary with the ringwork. The bailey is semi-circular in plan, the
enclosed area measuring approximately 80m east to west, and is surrounded by a
ditch with an internal bank. The bank and ditch are more pronounced on the
eastern side of the bailey. A narrow entrance at the south east corner of the
northern bailey is thought to represent an original access point, while
mounds adjacent to the entrance are thought to be the tower foundations of a
defensive gateway.

The southern bailey adjoins the south and east sides of the ringwork and is
thought to represent a subsequent phase of defensive work. The southern bailey
is kidney-shaped in plan, and the enclosed area measures approximately 140m
north east to south west and is surrounded by a deep ditch with a high
internal bank standing up to 5m above the bottom of the ditch. Mounds at the
edge of the bailey are thought to represent further tower foundations. A small
ditch and bank leads to the south from the south west corner of the bailey.
The area immediately to the west and south west of the southern bailey is
marked by a series of mounds and hollows thought to represent quarrying for
gypsum, an industry associated with the manor during the 14th century. The
western boundary of the monument is marked by an artificially enhanced
west-facing scarp.

All fences are excluded from the scheduling, although the ground beneath them
is included.

The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

Ringworks are medieval fortifications built and occupied from the late
Anglo-Saxon period to the later 12th century. They comprised a small defended
area containing buildings which was surrounded or partly surrounded by a
substantial ditch and a bank surmounted by a timber palisade or, rarely, a
stone wall. Occasionally a more lightly defended embanked enclosure, the
bailey, adjoined the ringwork. Ringworks acted as strongholds for military
operations and in some cases as defended aristocratic or manorial settlements.
They are rare nationally with only 200 recorded examples and less than 60
with baileys. As such, and as one of a limited number and very restricted
range of Anglo-Saxon and Norman fortifications, ringworks are of particular
significance to our understanding of the period.

The medieval ringwork and baileys at Castle Hills Wood survive well as a
series of earthwork and buried deposits. Documentary research and
archaeological survey mean that the site is quite well understood. The
artifically raised banks will preserve evidence of land use prior to their
construction. Its strategic position and later fortifications demonstrate its
continued importance as a feature of the wider medieval landscape. As a
high-status residence it contributes to our understanding of the social,
economic and military activities of a particular component of medieval

Source: Historic England


RCHM(E), Everson, P L and Taylor C C and Dunn, C J, Change And Continuity: Rural Settlement in North-West Lincolnshire, (1991)

Source: Historic England

Other nearby scheduled monuments is an independent online resource and is not associated with any government department. All government data published here is used under licence. Please do not contact for any queries related to any individual ancient or schedued monument, planning permission related to scheduled monuments or the scheduling process itself. is a Good Stuff website.