The coastal fortifications of Drake's Island

Reasons for Designation

Drake's Island controls the entrances to Plymouth Sound, the River Tamar and
the Cattewater and, in consequence, was of great strategic importance in the
defence of Plymouth city and its naval base. The island has a long history of
military use dating back to at least the 16th century when it acted as a major
link in the coastal defences during the period leading up to and immediately
following the Spanish Armada. The island played a vital role in the seige of
Plymouth in the Civil War and, from the early 18th century to the abandonment
of the coastal defence system in 1958, the island's sole role was in
safeguarding the approaches to Plymouth. The considerable diversity in
military architecture on the island and its longevity of use provides
important information on the technological development of coastal artillery in
works from the medieval period to more recent times. As such, the monument
demonstrates a very complete record of a major defensive fortification in all
its phases.

Details

Drake's Island stands as an imposing rock outcrop guarding the entrance to Plymouth Sound, and incorporates numerous defensive structures dating from the early post medieval period to the 20th century.

The island is some 2.6ha in total area, the majority of which is occupied by military monuments. The earliest remains are the base of a masonry tower on the NE corner of the island (SX46985286) and a seawall (SX46845290). The tower base is polygonal, containing a chamber with a corbelled roof, and is identified as a 16th century artillery tower. The seawall dates from the 17th century or earlier and also functioned as an artillery work as the blocked crenellations show. It is marked on a plan of 1716, and is the most substantial defence work of this date on the island.

Remains from the 18th century include a gatehouse and courtyard with fortified elements sited near the original jetty on a low cliff (SX46865287). The firing step of a small arms platform (SX46795289) survives along the northern wall, while the western wall contains musketry loops and a late 18th/early 19th century emplacement and magazine (SX46815284). This is one of two surviving gun emplacements belonging to the pre-Royal Commission armament (the second is at SX46925285). A curtain wall protects ground access from the eastern gun emplacements to the landing point and includes a walkway with further musketry loops.

The 19th century remains are extensive and include four gun batteries, one of which is the largest in the whole Plymouth defence system commanding the entire Sound (SX47005280). An ammunition hoist with a chain conveyor belt with wooden shell trays is still preserved in situ (SX46965280), plus a battery office with bomb roof (SX46815284), a crane (SX46905285), and extensive tunnels, stairways, gun emplacements and shell chambers (SX46965280).

Remains of the 20th century comprise two World War II gun emplacements (SX46795284) and brick built parapets with loops for Maxim guns of 1902-3 (SX47005276).

Although artillery fortifications of the island are first recorded around 1549, with the conversion of St Michael's chapel into a bulwark and fort, they were considerably strengthened immediately before and after the Armada (1588). In 1590 there were 23 guns on the island, the Governor of Plymouth Fort being responsible also for Drake's Island.

The island was held for Parliament during the Civil War siege of Plymouth (1643-6) and at the restoration became a state prison in which Parliamentarians were held, the most notable being Major General John Lambert. A survey by Col. Christian Lilly in 1716 records a fortification or "platform" running around most of the island's circumference. Substantial remains of these "platforms" and the entrance gateway complex survive, but the "castle" appears to have been destroyed during the construction of the mid-nineteenth century defences.

The late eighteenth century garrison was manned by the Royal Artillery. During World War II, two concrete mine control towers were built near the casemates and two "twin-6" guns were mounted as a defence against fast motor torpedo boats (E-boats). The monument includes 3 separate protected areas. An area at the western end of the island and lying inside the defences is excluded from the scheduling. Significant archaeological features are not presently known to exist in this area, with the exception of the major buildings for which protection under listing legislation is more appropriate.

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:

12614

Legacy System:

RSM

Sources

Other
Morley, B, AM7, (1977)
Weston, S M, AM107, (1984)
Mercer, RJ, AM7, (1973)

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