Amherst Redoubt is part of the Brompton or Great Lines, an C18th land defence system surrounding Chatham dockyard and barracks. The first phase of the lines, started in 1715 and completed by 1756, consisted of a series of unrevetted ditches and bastions running from the Ordnance Wharf to the Medway, enclosing Brompton. The ditches, 8 feet deep and 27 feet wide, and the earthen rampart, 9 feet high, survive largely intact.

Amherst Redoubt dates from this earliest phase of defensive works, it was constructed as an earthwork with surrounding ditch in 1756. From 1770 onwards it was rebuilt in brick with a connecting tunnel from the interior to the ditch. The guardhouse was built between c.1810-1820 (1). By the early 19th century it was part of Fort Amherst.

In 1981 a registered charity, The Fort Amherst and Lines Trust, was set up and in 1982 fourteen acres of the defences were purchased from the DOE. Scheduled, (Hornwork at the 'Couvre Port' not included). (2-3).

Alan Ward, 1994, The Amherst Redoubt Guardhouse: Examination of windows (Unpublished document). SKE15843.

<1> A Handbook of Kent's Defences 1540-1945 1977 12 (D Bennett) (OS Card Reference). SKE32802.

<1> Alan Ward, 1993, Fort Amherst & Lines Trust: The Amherst Redoubt Guardhouse (Unpublished document). SKE15842.

<2> A Handbook of Kent's Defences 1540-1945 1977 12 (D Bennett) (OS Card Reference). SKE32802.

<3> The Medway Forts: A Short Guide 1976 7-8 (K R Gulvin) (OS Card Reference). SKE50429.