From the National Heritage List for England: Details The monument includes a martello tower, set within a dry moat and situated above a steep, south facing slope, overlooking Sandgate and the sea beyond. The tower, which is Listed Grade II, is one of a cliff top series of six moated towers, constructed in 1805-6 to defend the coastline between Hythe and Folkestone, and lies around 360m north east of tower no 7. The slightly elliptical, brick built tower measures up to 13m in diameter externally and stands complete to its original height of about 10m. The upper half of the tower protrudes above the lip of the brick retaining wall of the moat, which encircles the base at a distance of around 10m and was intended to provide further protection against both cannon fire and ground assault. The tower was constructed on three levels, with battered (inwardly sloping) walls, designed to deflect cannon shot, ranging from around 1.6m to 4m in thickness, the most substantial section being the wall base on the southern, seaward side. The external face of the tower was rendered in a cement mortar, or stucco, which served to strengthen the outer skin of bricks, and traces of this survive. A thick central column rises from the basement to the top of the tower, from which springs the barrel vaulted first floor ceiling which supports the gun platform on the roof. Access into the tower is by way of a first floor doorway to the north, which was originally approached by a footbridge which spanned the moat. The section nearest the tower was designed as a drawbridge, capable of being raised to seal the entrance. The bridge does not survive, although part of the mechanism used to raise it remains in place. The doorway is headed by a stone tablet which originally displayed the number of the tower. The first floor was divided into three rooms by wooden partitions and provided accommodation for the garrison of 24 men and one officer. Two fireplaces heated the rooms, which were lit by two splayed window openings to the east and west. The ground floor was reached by a trap door near the entrance, leading down through a suspended timber floor. This was used to store ammunition and supplies, and provision for these includes a vaulted magazine, partly recessed into the thickness of the outer wall. Safety features included a lantern window in a partition wall, separated from the magazine by panes of glass. Ammunition lift shafts, linking the gun emplacement to the basement level, were also inserted into the thickness of the wall during later, 19th century refurbishments. The open gun platform is reached from the first floor by an internal stone staircase constructed in the thickest part of the tower wall. The circular roof space, designed to accommodate a 24-pounder cannon mounted on a wooden traversing carriage, retains most of its original features, including the central gun pivot and perimeter step, with both inner and outer iron running rails in place. Four ammunition stores in the form of arched recesses, and a smaller niche, thought to have housed a gunpowder flask and later modified to form the head of a lift shaft, also survive within the parapet wall which encircles the roof. A brick stack, over one of the original chimney positions in the parapet coping stones, also remains in place. The cannon, which had a range of around 1.5km and could be turned through 360 degrees, was operated by a series of rope pulleys, and the six iron hauling-rings used for traversing and preparing the cannon, are set into the parapet wall which encircles the roof. All modern fixtures and fittings, such as the modern danger signs and materials used to seal the door and window openings are excluded from the scheduling, although the structures to which they are attached are included. Also excluded are the modern fences, although the ground beneath them is included Reasons for Designation Martello towers are gun towers constructed to defend the vulnerable south eastern coast of England against the threat of ship-borne invasion by Napoleonic forces. Built as a systematic chain of defence in two phases, between 1805-1810 along the coasts of East Sussex and Kent, and between 1808- 1812 along the coasts of Essex and Suffolk, the design of martello towers was based on a fortified tower at Mortella Point in Corsica which had put up a prolonged resistance to British forces in 1793. The towers take the form of compact, free-standing circular buildings on three levels built of rendered brick. The towers of the south coast were numbered 1-74 from east to west, while those of the east coast were identified by a system of letters (A-Z, and then AA-CC) from south to north. Although they exhibit a marked uniformity of design, minor variations are discernible between the southern and eastern groups and amongst individual towers, due mainly to the practice of entrusting their construction to local sub-contractors. Most southern towers are elliptical in plan, whilst the eastern group are oval or cam-shaped externally, with axes at the base ranging between 14.4m by 13.5m and 16.9m by 17.7m. All are circular internally, the battered (inwardly sloping) walls of varying thicknesses, but with the thickest section invariably facing the seaward side. Most stand to a height of around 10m. Many martello towers are surrounded by dry moats originally encircled by counterscarp banks, and/or have cunettes (narrower water defences) situated at the foot of the tower wall. The ground floor was used for storage, with accommodation for the garrison provided on the first floor, and the main gun platform on the roof. The southern towers carried a single 24 pounder cannon, whilst the eastern line carried three guns (usually a 24 pounder cannon and two shorter guns or howitzers). Three large, circular ten- gun towers known as redoubts were also constructed at particularly vulnerable points, at Dymchurch, Eastbourne and Harwich. All three survive. As the expected Napoleonic invasion attempt did not materialise, the defensive strength of the martello tower system was never tested, and the tower design was soon rendered obsolete by new developments in heavy artillery. Many were abandoned and fell into decay or were demolished during the 19th century, although some continued in use into the 20th century as signalling or coastguard stations and a few saw use as look out points or gun emplacements during the two World Wars. Of the original 74 towers on the south coast, 26 now survive, and of the 29 on the east coast, 17 now survive. Those which survive well and display a diversity of original components are considered to merit protection. Martello tower no 6 survives well, and retains many of its original components and associated features. When viewed as one of a series of six cliff top towers, no 6 illustrates the strategically planned integration of the martello tower system and provides a valuable insight into the defence of Britain during the 19th century.