Sheerness lies on the edge of the Isle of Sheppey, where the River Medway flows into the Thames Estuary. A Royal Navy dockyard was established there in the 1660s. After a Dutch raid in 1667 the site's fortifications were improved including the construction of a flooded ditch. The name 'Blue Town' originates from the blue-grey naval paint used to cover the cabins built by dockyard workers. The dockyard closed almost thee hundred years later in 1960.
Historic England Archive EAW037832.