The Moat’s Bulwark was built by Henry VIII as part of artillery fortifications intended less as a strengthening of the castle than as protection for the newly enlarged harbour. These fortifications took the form of comparatively small block houses or batteries: Archcliffe Fort under the Western Heights, the Black Bulwark on the Pier, Moat’s Bulwark below the castle cliff and a third bulwark in the castle moat.Moats Bulwark has been greatly altered and little of the original structure remains. It is first mentioned as ‘the bulwark subtus castrum Doveri’ and was probably built circa March 1539, when Charles de Marillac, the French Ambassador, saw ‘the new ramparts and bulwarks in the rock where the sea beats’. It had ordnance and artillery and a captain at least by 1540. Of timber construction at a cost of about one-third of £1496 (the total recorded cost of the three bulwarks), it appears on a sixteenth century map as a timber revetted platform, with a roughly circular front, approached by tunnels in the cliff.The large semicircular battery which is now the most obvious feature, dates from the invasion scares of the 1740s when the harbour defences from Archcliffe Fort to Moat’s Bulwark were strengthened and barracks built at both places.An account of about 1772 describes it thus:'Although dependent on the castle, it has its peculiar officers; there are a captain, lieutenant, and master-gunner. It consists of a gate, having rooms over and on both sides of it, a house for the gunner, and a circular stone battery, to which there is a descent by a flight of steps. The entrance is on the east side, by a gradual ascent formed out of the chalk. A gunner, who formerly resided here, with great industry embellished the sides of the cliff with several parterres of flowers, which had a very pleasing effect: indeed, both the forms and situation of these buildings conspire to render the view extremely picturesque and romantick’.Between 1775 and 1783 Moat’s Bulwark and Achcliffe Fort were again overhauled and their defences updated. In front of Moat’s Bulwark, the Guilford Battery was built, armed with four 32 pdr guns and a number of carronades. Along the waterfront were built a further three detached works, known as North, Townsend and Amherst batteries, all of which had much the same armament. With the exception of some of the nineteenth century buildings associated with Guilford Battery, no trace of any of these now remains. In 1853-4 Guilford Battery had its parapets raised and 42pdr guns installed on traversing mounts. At the same time a certain amount of modernisation work was carried out on Moat’s Bulwark. In 1856 a spiral stairway of 214 steps was cut inside the cliff, just south of Canon’s Gate, to link Moat’s Bulwark and Guilford Battery to the castle. At intervals defensible landings and doorways with firing slits were incorporated, while lighting passages led to openings in the cliff face. In the Second World War, some of the latter were converted to observation posts and had short accommodation tunnels added to their rear.In 1908 Moat’s Bulwark passed to the care of the Ancient Monuments Branch of the Ministry of Works and its military career was at an end. It is now hemmed in between the A20 and the cliff, a neglected ruin. In another town that does not have major historical sites like the Castle and the Western Heights more would be made of remains like this but poor old Moat’s Bulwark is just a bit over shadowed by it’s big brothers.