Grain Fort is a former artillery fort located just east of the village of Grain, Kent. It was constructed in the 1860s to defend the confluence of the Rivers Medway and Thames during a period of tension with France. The fort's location enabled its guns to support the nearby Grain Tower and Garrison Point Fort at Sheerness on the other side of the Medway. It was repeatedly altered and its guns upgraded at various points in its history, before being decommissioned in 1956 when the UK abolished its coastal defence programme. It was subsequently demolished. The remnants of the fort are still visible and have been incorporated into a coastal park. Strategic context The fort was constructed in response to a naval arms race between Britain and France. Britain's coastal defences had not been substantially upgraded since the Napoleonic Wars, but a new generation of accurate and powerful guns, mounted on fast-moving, manoeuvrable iron-clad warships, had obsoleted the existing 18th and early 19th century forts along the British coastline. The Thames was seen as particularly vulnerable; as well as being one of the country's most important trade routes, it possessed several naval installations of great importance, including the victualling yards at Deptford, the armaments works of Woolwich Arsenal, the shipbuilding yards at North Woolwich, and the magazines at Purfleet. The government's response to the increased threat was to appoint a Royal Commission on the Defence of the United Kingdom, which published a far-reaching report in 1860. It recommended that many existing forts should be upgraded or rebuilt entirely, and that new forts should be constructed to guard particularly strategic or vulnerable points along the coast. In all, around 70 forts and batteries were constructed around the English coast as a result of the Royal Commission's report. An existing gun battery, Grain Tower, already existed just off the shoreline at Grain, about away from the site of the later Grain Fort. It had been built in the style of a Martello tower between 1848 and 1855 but the introduction of powerful and accurate rifled muzzle loader (RML) guns during the 1850s made it obsolete as soon as it was completed. The 1860 Commission report recommended that Grain Tower should be turned into a fully casemated fort, which would be built around the existing structure. However, the cost of doing this was seen as excessive and the proposal was dropped as part