Mobbs Hole moated site and decoy pond, Ashwell
Listed on the National Heritage List for England. Search over 400,000 listed places
Overview
- Heritage Category:
- Scheduled Monument
- List Entry Number:
- 1012306
- Date first listed:
- 17-Oct-1990
Location
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Discover moreOfficial list entry
- Heritage Category:
- Scheduled Monument
- List Entry Number:
- 1012306
- Date first listed:
- 17-Oct-1990
Location
The building or site itself may lie within the boundary of more than one authority.
- County:
- Hertfordshire
- District:
- North Hertfordshire (District Authority)
- Parish:
- Ashwell
- National Grid Reference:
- TL 26356 43776
Reasons for Designation
Around 6,000 moated sites are known in England. They consist of wide ditches, often or seasonally water-filled, partly or completely enclosing one or more islands of dry ground on which stood domestic or religious buildings. In some cases the islands were used for horticulture. The majority of moated sites served as prestigious aristocratic and seigneurial residences with the provision of a moat intended as a status symbol rather than a practical military defence. The peak period during which moated sites were built was between about 1250 and 1350 and by far the greatest concentration lies in central and eastern parts of England. However, moated sites were built throughout the medieval period, are widely scattered throughout England and exhibit a high level of diversity in their forms and sizes. They form a significant class of medieval monument and are important for the understanding of the distribution of wealth and status in the countryside. Many examples provide conditions favourable to the survival of organic remains.
Mobbs Hole is a good example of a double island moated site with an unusual association with a decoy pond.
Details
The monument includes the well-defined remains of a double island moated site and adjacent decoy pond. The moated site comprises a small enclosure, measuring some 55m by 40m, located within the western corner of a larger enclosure, measuring 90m by 65m in external dimensions (inclusive of both 7m wide surrounding waterfilled moats). The interiors of the moated islands are flat apart from the remains of modern upcast banks from recent dredging. A linear decoy pond is attached to the south corner of the moated site. The pond measures some 100m in length and varies between 10m and 6m in width tapering off towards its south-eastern end. The pond is thought to have been constructed for trapping waterfowl but may also have functioned as an outflow channel from the moats.
MAP EXTRACT The site of the monument is shown on the attached map extract.
Legacy
The contents of this record have been generated from a legacy data system.
- Legacy System number:
- 11557
- Legacy System:
- RSM
Sources
Other
NAR Records, (1972)
NAR Records,
Murfitt, C M Mr, Information on Artifacts, (1989)
Legal
This monument is scheduled under the Ancient Monuments and Archaeological Areas Act 1979 as amended as it appears to the Secretary of State to be of national importance. This entry is a copy, the original is held by the Department for Culture, Media and Sport.
Map
This map is for quick reference purposes only and may not be to scale. This copy shows the entry on 29-Jun-2026 at 20:42:20.
Download a full scale map (PDF)End of official list entry
All text content is available under the Open Government Licence v3.0 , except where otherwise stated. Any supplied maps are © Crown Copyright [and database rights] 2026 OS AC0000815036 and may not be reproduced without permission.