New Tavern Fort is an historic artillery fort in Gravesend, Kent. Dating mostly from the 18th and 19th centuries, it is an unusually well-preserved example of an 18th-century fortification and remained in use for defensive purposes until the Second World War. It was built during the American War of Independence to guard the Thames against French and Spanish raiders operating in support of the newly formed United States of America. It was redesigned and rebuilt in the mid-19th century to defend against a new generation of iron-clad French warships.

By the start of the 20th century, the Thames defences had been moved further downriver to the estuary and the fort was disarmed. Its grounds were opened to the public as pleasure gardens, but the fort was temporarily taken back into military use during the Second World War. Today the fort and its magazines and other underground structures have been restored and are open to the public. It is unique in the UK for its display of guns and emplacements ranging from the 18th to the 20th centuries.

The fort is situated on the south bank of the River Thames, intended to support the much older Tilbury Fort on the north bank. The structure consists of a broad earthen rampart constructed in a zig-zag pattern, with a broad ditch in front of it. Eight emplacements, six of brick and two of concrete, are contained within the rampart with magazines underneath them. The interior of the fort - originally its parade ground - is occupied by a grass-covered lawn with flowerbeds, trees, ornamental bushes and a bandstand at the centre.

The lower Thames was of great strategic significance as the location of major military installations including the dockyard and arsenal at Woolwich, the powder magazine at Purfleet, and the victualling stores and shipyard at Deptford. In addition, it was essential to ensure that an enemy could not make a landing along the Thames, which offered a potential land corridor to London.[5] The crossing between Gravesend and Tilbury was also of considerable importance, which had prompted the Tudors to build fortifications on both sides of the river at that point.

The fort was constructed between 1780 and 1783 on a site originally occupied by the New Tavern Inn, from which it took its name. As the land was private property occupied by a Mr. Houghton, a vesting act (the Plymouth, Sheerness, Gravesend, Tilbury – Fortifications Act 1780, 20 Geo. 3. c. 38) was passed to purchase it.[9] It was originally an irregularly shaped unrevetted earthwork consisting of two batteries linked by a rampart.[1] The first battery had two faces forming an angle towards the river, while the second smaller battery had a straight front. It was protected on the riverside by a flat-bottomed ditch within which was a pallisade made of timber standing about 3 metres (9.8 ft) high.[10] The two batteries were armed with fifteen heavy guns (24 and 32 pdrs.) which fired through embrasures

Milton Chantry was incorporated into the fort's perimeter and was converted into an artillery barracks. By the 1790s, additional buildings had been constructed, including quarters for the commanding officer, stables and magazines.[1] The rear of the fort was originally open,[10] but by the end of the 18th century a defence wall and caponier with loopholes for muskets had been built to close it off.[1] A kiln was also built to heat shot to a red heat for setting ships on fire