A vision of wartime history is emerging on Suffolk’s changing coastline.

The Second World War defences that protected Britain’s shoreline have been uncovered during a coastal conservation project.

Touching the Tide, a £900,000 scheme funded by the Heritage Lottery and The Crown Estate, is working with the county council’s archaeological service to explore the remains.

Three sample surveys at Bawdsey, Sizewell and Walberswick have revealed reminders of Britain’s preparations to prevent invasion, and of the pace and extent of coastal change over the last 70 years.

At Bawdsey, the survey revealed square concrete bases known as Admiralty scaffolding, designed to impede seaborne invasion.

Also uncovered were a number of pillboxes originally positioned at the cliff-top but now some distance down the beach due to erosion, which research indicates has moved the shoreline 260 metres since the 1940s.

The Sizewell survey revealed several reinforced concrete cubes, which would have been among thousands of anti-tank defences cast in situ and set three to four deep on beaches across Britain. While some remain visible, others are partly buried in the sand dunes, with a some having tumbled on to the beach.

At Walberswick, the position of anti-tank cubes south of Valley Farm has been compared with aerial photos from the 1940s. While many remain standing, it is thought that pillboxes and scaffolding recorded at the time have submerged about 50m off shore.

Bill Jenman, project manager at Touching the Tide, which was set up in Spring 2013 to help celebrate and conserve the heritage of the Suffolk coast, and increase understanding of coastal change, said: “We know that all sorts of military buildings and equipment were left behind after World War Two. Looking at pillboxes out at sea is a graphic illustration of just how rapidly this coast is changing.”

Suffolk has one of the most unsettled coastlines in Britain, with experts reporting new beach growing along a third of the shoreline while 46% erodes.

Gary Thompson, The Crown Estate’s coastal and stewardship manager, said: “This project has given us a fascinating insight into the nation’s wartime preparations and provided a reliable data source charting the effects of erosion and coastal morphology along the Suffolk coastline since the 1940s.”

The Crown Estate’s Marine Stewardship Fund, established in 1999, supports community initiatives and scientific research that help promote the long-term sustainable management of marine environments.