RCHME survey of the earthworks and structures associated with the coastal batteries at Grain, on the Isle of Grain, Kent. The fortifications on Grain were of paramount importance, protecting the mouth of the River Medway along with the fortifications at Sheerness. Thus, they were a vital link in the East Coast defences. The visible remains of the Grain defences comprise five batteries of coastal artillery, one of which was a powerful garrisoned Fort, another a Tower, which lies in the estuary on Grain Spit. The five are named, Grain Fort, Grain Battery, Wing Battery, Grain Tower and Dummy Battery. The report deals with each battery in turn.