The Palmerston Forts, constructed to encircle Plymouth and to protect the Royal Dockyard against a landing by the French, were built during the 1860s and 1870s following a Royal Commission set up by the then Prime Minister Lord Palmerston (hence the name).
The Commission was prompted by public concern about the growing military and naval power of the French Empire, coupled with the alarm which had been engendered in Britain when Napoleon III (the nephew of the infamous Napoleon Bonaparte) became Emperor of France in 1852. A perception arose that Napoleon III might contemplate an invasion of Britain in order to avenge the defeat and exile of his uncle in 1815.
As a result, the Commission, of 1860, sanctioned the provision of enormous resources for the defence of the principal naval dockyards on the south coast, these being Portsmouth and Plymouth. Many of the Palmerston Forts survive well as Scheduled Monuments (designated as such by Historic England) and are therefore recognised as nationally important and worthy of preservation.
The forts may be divided broadly into two groups classified by their defensive purposes:
The coastal defences were based on an inner and an outer line with new batteries constructed at Bovisand, Picklecombe and just behind the Breakwater on the outer line. Some of the earlier defensive structures of Plymouth and its harbour such as the Citadel were also brought into play as components of the inner line.
The land defences were constructed specifically to protect Plymouth from an enemy landing somewhere further up or down the coast and thus threatening the dockyard from the rear. The chain of forts and batteries were divided by the estuaries of the Lynher, Hamoaze and Cattewater, with three principal forts based at Staddon on the east, Crownhill in the centre and Tregantle in Cornwall on the west providing the anchor points for the 17 or so forts and batteries of the land defences. Crownhill Fort is the best known of the landward forts due to its remarkable state of survival and its accessibility. Less well known is the fact that all of the forts and batteries of the north east defences stretching from Ernesettle in the west to Laira in the east were linked by a military road, the route of which still survives as the modern Crownhill Road and Fort Austin Avenue, whilst at Laira it has retained its original name of Military Road to this day. The forts were also linked by massive ditches and earthworks, most of which have disappeared, although some of the earthworks linking Ernesettle Battery and Agaton Fort may be seen to the west of St Budeaux Church.
The extent of care or repair ideally needed for each of the forts varies greatly from one site to the next. In fact the range of uses that these structures have been put to is diverse and each type of use can bring its attendant problems, in addition to the day-to-day maintenance required to keep them functioning as useful buildings. All of the forts are in beneficial ownership of one kind or another, whether this be public or private. However an overall management strategy for their well being based upon recognition of their original purpose and the common management problems encountered would be a step forward.
In a recent characterisation study of Plymouth undertaken on behalf of English Heritage, the Palmerston Forts, particularly those of the north east defences, were recognised as contributing towards the development of the neighbourhoods to the north of the city, due to the existence of the major east/west route created by the linking military road. This study has raised the profile of the Palmerston Forts and has led English Heritage to call for more detailed studies of the contribution that the forts make to the heritage of northern Plymouth and to the city as whole, and to their consideration within local area action plans.