Mount Pleasant Redoubt

Reasons for Designation

Redoubts are defensive outworks, usually square or polygonal in shape, and without any flanking defences. Constructed as earthworks or of stone, or a combination of the two, they were often sited at strategic locations forward of the main defences in order to command the easiest approaches and thus deter the enemy from making any direct assault. Landward gun-mounted redoubts were not heavily defended against attack but relied on their prime location and firepower to keep any potential enemy at a distance. Mount Pleasant Redoubt survives as a nearly complete example in plan of a forward redoubt of late 18th century date with many of its original features still visible and with its strategic location commanding the approaches to the dockyard and Dock Lines still able to be appreciated. Although there has been some modification, additions, and repairs of the interior during post-war measures to incorporate the redoubt into a public park amenity, Mount Pleasant Redoubt survives well. It serves as a visual reminder of the importance of the Plymouth Dockyard as a major base of Britain's naval power in the 18th and 19th centuries and illustrates the steps which were taken to protect it from land invasion. The redoubt is sited in public open space and has been provided with comprehensive information boards explaining how the redoubt operated and its place within the defences of Plymouth.

Details

The monument includes Mount Pleasant Redoubt, a square earthwork redoubt constructed in the late 18th century and designed to hold a battery of guns in an advanced position forward of the defences of the Plymouth Dockyard (known as the Dock Lines). It was sited in a commanding location on the watershed between two valleys leading down to the River Tamar and Stonehouse Creek and the redoubt was intended to cover the easiest landward approach to the dockyard. It was part of an integrated defensive system intended to protect the dockyard against the threat of a land invasion by Franco-Spanish forces during the period of uncertainty caused by the American War of Independence (1775-83) and it stood about 0.5km to the north east of the Dock Lines. The monument is Listed Grade II. The Mount Pleasant Redoubt was first proposed by Dixon in January 1780 and it appears to have been completed by March of that same year. It is defined by an earth bank about 42sq m with a single entrance cut through on the south side. The entire redoubt was surrounded by a 5m wide ditch and a counterscarp bank which are still visible over most of their length although the ditch has been partly filled. The inner face (scarp) of the ditch was revetted in brick, a substantial section of which survives at the north west corner. The outer face (counterscarp) of the ditch consisted of a battered masonry wall of which only some sections remain visible. Access across the ditch and into the redoubt was via a drawbridge. A glacis or landscaped area to provide a clear field of fire was created around the redoubt. The redoubt was armed with guns which were mounted on the two front faces, those facing north and east, en barbette, that is with the guns able to fire over the low parapet wall without the need for embrasures or gaps in the parapet. By 1787 the redoubt had eleven 18-pounders and by 1811 the terreplein (the level area where the guns are mounted) was resurfaced in stone and eleven individual gun positions were reported. The rear two faces (western and southern) did not have mounted cannon as they formed the rear of the position. However, they were provided with infantry banquettes, firing steps on the interior of the rampart along which the troops could deploy with light arms. In the centre of the redoubt was a two-storey blockhouse which was burnt out in 1855 and no longer survives above ground, although its below ground room most likely survives. It was connected via an underground passage or souterrain to the main magazine in the south west corner of the rampart which has been blocked off and is not accessible. As a result of the Royal Commission of 1860 a new line of defences for the dockyard was created much further out. Mount Pleasant Redoubt was intended to provide a rear support for these defences but in the event it became redundant although as late as 1885 its potential armament was still being discussed. In World War II the position was utilised for at least one anti-aircraft gun and a barrage balloon was anchored to the remains of the blockhouse whilst a civilian air-raid shelter was constructed in the lee of the glacis alongside Masterman Road. After the war the blockhouse was demolished and the redoubt and its surroundings incorporated into a public park.

Several features are excluded from the scheduling. These are: all fixed benches, fixed signposts, modern brick steps, modern brick information plinths, modern entrance walling, modern paths, surfaces and hardstanding, all playground furniture, and all fencing. The ground beneath all of these features is, however, included.

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:

33071

Legacy System:

RSM

Sources

Books and journals
Pye, A, Woodward, F, The Historic Defences of Plymouth, (1996), 166
Pye, A, Woodward, F, The Historic Defences of Plymouth, (1996), 164-66
Pye, A, Proceedings of the Devon Archaeological Society in An archaeological survey of Mount Pleasant Redoubt, Plymouth, Vol. 50, (1992), 137-161

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