Sandown Castle


Heritage Category:
Scheduled Monument
List Entry Number:
Date first listed:


© Crown Copyright and database right 2021. All rights reserved. Ordnance Survey Licence number 100024900.
© British Crown and SeaZone Solutions Limited 2021. All rights reserved. Licence number 102006.006.
Use of this data is subject to Terms and Conditions.

The above map is for quick reference purposes only and may not be to scale. For a copy of the full scale map, please see the attached PDF - 1005147.pdf

The PDF will be generated from our live systems and may take a few minutes to download depending on how busy our servers are. We apologise for this delay.

This copy shows the entry on 17-Apr-2021 at 14:56:40.


The building or site itself may lie within the boundary of more than one authority.

Dover (District Authority)
Dover (District Authority)
National Grid Reference:
TR 37588 54306


Sandown Castle 458m ENE of Barns Close.

Reasons for Designation

Artillery castles were constructed as strong stone defensive structures specifically to house heavy guns. Most date from the period of Henry VIII's maritime defence programme between 1539 and 1545, though the earliest and latest examples date from 1481 and 1561 respectively. They were usually sited to protect a harbour entrance, anchorage or similar feature. These monuments represent some of the earliest structures built exclusively for the new use of artillery in warfare and can be attributed to a relatively short time span in English history. Their architecture is specific in terms of date and function and represents an important aspect of the development of defensive structures generally. Although documentary sources suggest that 36 examples originally existed, all on the east, south and south east coasts of England, only 21 survive. All examples are considered to be of national importance.

The castle is one of three making up a distinctive and well known group of coastal fortifications. Together these illustrate the strategic role assigned to this stretch of coast during the 16th century.

The history and development of Sandown artillery castle is documented by many contemporary records and illustrations, providing evidence for its original layout and the changing function of the monument over five centuries. Despite having been partly demolished, a large part of the footings and original fabric of the castle survive as buried remains which will provide further information about the construction, use and history of the castle.


See Details.


This record was the subject of a minor enhancement on 17 March 2015. This record has been generated from an "old county number" (OCN) scheduling record. These are monuments that were not reviewed under the Monuments Protection Programme and are some of our oldest designation records.

The monument includes an artillery castle surviving as upstanding and below-ground remains. It is situated on the low-lying east Kent coast, near Tenants Hill to the north of the modern seaside town of Deal.

The castle has been part demolished and largely survives as buried remains, although part of the footings still remain. A rockery has been built upon the western part of the castle and it has also been partly incorporated into the modern sea wall. The surviving remains include a segment of the central keep and the south-west and north-west bastions. The basement of the keep includes several springers for a ribbed and vaulted ceiling. The remains of a vaulted gallery, with small chambers leading off, runs around the interior of the surviving bastions. There is also evidence of a moat on the north-west side, although it largely survives as a buried feature having become in-filled in the past.

The castle is one of a group of three, the other two being located at Deal and Walmer, 2km and 4km to the south respectively. The castles were built between 1539-40 by Henry VIII in order to protect the shallow semi-sheltered anchorage between the Goodwin Sands and the coast, known as the Downs. This was of great strategic importance because, by the 16th century, there were few other safe places of refuge for ships along the channel coast between Kent and Portsmouth. The castles of the Downs were built in the face of the political crisis and consequent fear of invasion occasioned by the king's divorce of Catherine of Aragon in 1533. They were financed from the proceeds raised by the Dissolution of the Monasteries.

A number of early plans and views of the castle provide information on its original form. It was very similar to Walmer Castle with a circular keep surrounded by four bastions separated by an inner moat and surrounded by an external moat. The entrance was by a drawbridge on the landward side. The upper part of the central keep contained a water cistern and below it was a vaulted apartment for the garrison. The outer bastions were massive structures each with a gun room at ground level and a gun-platform on the roof to mount artillery on. The moat was protected by a tier of hand-guns firing from a gallery running around the whole castle at basement level. There were 39 gun ports for heavy armaments and 39 hand-gun loops to control the moat. In addition to the three castles there were four earthen bulwarks protecting this area of the coast.

These were observed by William Stukeley and Edward Hasted in the 18th century. They included the ‘Great Bulwark of Turf’ and the ‘Little Bulwark of Turf’ between Sandown and Deal Castles, and the ‘Great White Bulwark of Clay’ and ‘Walmer Bulwark’ between Deal and Walmer. All of the fortifications were linked by a curved trench forming a single defensive line extending about 4km along the coastline.

Queen Elizabeth I apparently lodged at Sandown Castle in 1588. The castle saw no action until the Civil War when, during the Royalist revolt in Kent in 1648, the castles of the Downs were captured and held out against Parliamentary forces for several weeks. During the Anglo-Dutch Wars they performed their intended role in protecting shipping in the Downs and Sandown is reported as firing on a man-of-war attacking small craft. However by this time the castles were becoming increasingly obsolete as fortifications. Sandown was particularly vulnerable to coastal erosion and storms. In 1785 the sea broke into the moat and it was declared unfit for habitation. It was repaired in 1808 and the castle was garrisoned during Napoleonic Wars. It was still fairly complete in 1855 when the last captain of the castle, Sir John Hill, died. Subsequent erosion and fire damage led to it being sold by the War Office as building material in 1863 and by 1882 a large part had been dismantled. The stone was re-used in the gatehouse of Walmer Castle and in the ornamented gardens and rockery, which are now situated on the western side of the castle.


The contents of this record have been generated from a legacy data system.

Legacy System number:
KE 176
Legacy System:


Kent HER TR 35 SE 1. NMR TR 35 SE 1. PastScape 468373


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 Digital, Culture, Media and Sport.

End of official listing

Your Contributions

Do you know more about this entry?

The following information has been contributed by users volunteering for our Enriching The List project. For small corrections to the List Entry please see our Minor Amendments procedure.

The information and images below are the opinion of the contributor, are not part of the official entry and do not represent the official position of Historic England. We have not checked that the contributions below are factually accurate. Please see our terms and conditions. If you wish to report an issue with a contribution or have a question please email [email protected].