Visitors can now see rare remains from the Second World War via a path which has been built to serve a new housing estate.
The so-called Tett Turrets at Docking, near Hunstanton, are among the last of their kind.
Just a handful of similar defences were built, while few have survived the centuries.
Their concrete domes would have provided a firing point akin to an armoured foxhole from which a soldier or member of the village's Home Guard could let fly at the enemy.
But they were abandoned after the threat of German invasion receded, as the Allies turned the tide on the Nazis.
The modest Grade II listed structures were forgotten to all apart from a few villagers as trees and scrub grew around them.
But the site was cleared for posterity after a developer built homes on the field next door, with the parish council taking ownership of a narrow strip of land which can now be accessed via a cycle path which leads off Well Street near the village school.
An interpretation board has also been installed to tell visitors about the history of what must be one of the smallest preserved wartime sites.
WHY THEY WERE BUILT
Docking might seem like any other rural Norfolk village, whose patchwork of fields were a world away from the conflict that raged across Europe.
But the RAF flew anti-shipping and weather patrols from a grass areodrome off the road to Brancaster to the north of the modern-day settlement.
And the village itself was considered of strategic importance belying its size, with fewer than 1,000 inhabitants once many of its men had signed up to fight.
For military planners feared the gently-shelving beaches of the nearby coast would be ideal terrain for a German invasion, from which its army could press south.
Docking sat on a vital crossroads, where roads from Heacham and Brancaster met on route to all points south and east.
So the village was fortified with pillboxes, walls along its main street were reinforced with tonnes of concrete to form makeshift firing points and the Tett turrets were sited on the edge of a wood with a short connecting tunnel.
SHORT-LIVED DEFENCES
Tett Turrets were designed in 1940 but were installed at just six sites including Docking before the design was abandoned in favour of the more substantial pillbox.
While their modest domes could swivel to allow rifle fire in multiple directions, the War Office soon abandoned the design, because it was cramped and offered little protection against bullets or grenades.
Other known surviving examples are found only at former RAF Hornchurch in Essex and at two sites in Hertfordshire.
Now listed as Grade II structures by Historic England, the turrets are described as "evocative reminders of the early part of the Second World War when enemy invasion from mainland Europe was widely anticipated".
