An artillery castle, known as Portland Castle, situated along the northern shore of the Isle of Portland. It represents one of a pair (the other is Sandsfoot Castle) of coastal fortifications constructed during the reign of Henry VIII in order to provide protection for the sheltered waters of Weymouth Bay. The two forts are sited on opposite sides of the bay and are inter-visible. Portland Castle has a central citadel which is fan shaped in plan. The structure is composed of ashlar dressed Portland Stone producing a rounded external appearance. The citadel includes a single storey gun room facing across the Romano-British harbour. The gun room was originally roofed and has embrasures for a further battery of five guns protected by an embattled parapet. This also shielded a second battery situated on the roof of the accommodation block. To the south and south east of the citadel was an outer yard which contained two gun platforms. The construction of the fortification followed the advice of a Commission set up by Henry VIII in 1539, in response to a possible French invasion. It was thought to be have been complete by late 1540 and in service by early 1541. During the Civil War the castle was the scene of some fighting, after which it was used as an ordnance store and later a prison. During the 19th century, the citadel was occupied as a residence, when wood panelling was first added to the interior. The structure is Scheduled and Listed Grade I It is also in the care of the Secretary of State and is open to the public
| --- | SDO23 - Serial: Dorset Natural History and Archaeological Society. 1914. Proceedings of the Dorset Natural History and Antiquarian Field Club. 35. 34-40 |
| --- | SDO150 - Bibliographic reference: Royal Commission on Historical Monuments (England). 1970. An Inventory of Historical Monuments in the County of Dorset. Volume Two (South East) Part III. |
| <1> | SWX1176 - Map: Ordnance Survey. Various. Ordnance Survey Map 1:10 000. 1:10 000. 1974 edition OS map |
| 2a | SWX1623 - Article in serial: Symonds H. 1914. Sandsfoot and Portland Castles. Vol 35. p34 |
| 2b | SWX1951 - Monograph: Ministry of Works. 1965. Portland Castle Official Guide. |
| <3> | SWX1955 - Monograph: List of ancient monuments in England: Volume 1, Northern England; Volume 2, Southern England; Volume 3, East Anglia and the Midlands Vol 3 Page(s) 82. Vol 3. |
| <4> | SWX1956 - Unpublished document: 1980. Field Investigators Comments F1 JB. 07-JUL-80 |
| <5> | SWX1957 - Monograph: 1982. The history of the Kings Works Vol 4 : 1485-1660. Vol 4. p399,404-405,466-70 |
| <6> | SWX1958 - Monograph: Coast defences of England and Wales, 1856-1956. Vol 1974. p228-9 |
| <7> | SWX1959 - Article in serial: Notes and queries for Somerset and Dorset: Vol 30.. Vol 30. p155-7 |
| <8> | SWX1960 - Monograph: HMSO. 1967. Maps and Plans of the Public Record Office. p303 |
| <10> | SWX1962 - Scheduling record: DCMS. 1997. Scheduled Monument Notification 25/09/1997. |
| <11> | SWX1963 - Monograph: A Teachers Handbook to Portland Castle. |
| <12> | SWX4013 - Index: Castellarium Anglicanum : an Index and Bibliography of the Castles in England, Wales and the Islands.. Vol I. p127 |
| <13> | SWX8579 - Unpublished document: Ancient Monuments Laboratory. 2000. Tree-ring Analysis of a Timber from Portland Castle, Castleton, Dorset. 62/2000. |
| <14> | SWX2185 - Scheduling record: DOE (HRR). 17 May 1993. List of Buildings of Special Architectural or Historic Interest: Borough of Weymouth and Portland amendment 1993. Vol 961. |
| <15> | SWX8592 - Unpublished document: Terrain Archaeology. 2001. Osprey Quay, Portland, Dorset: Archaeological Impact Assessment.. 5085.1. |