If you walk along the road between Trehan and Trematon there is a gate on the west side of the road with a warning sign. This is the site of ‘Winstone Beacon Reservoir'. Now operated by SWW it was originally opened by the Mayor of Saltash for the Borough of Saltash in November 1957.

In 1959 the ‘Cold War’ was at its height, the government constructed a network of underground bunkers that were usually manned 24 hours a day by the ROC (Royal Observer Corp) with assistance from local reserve volunteers. Their purpose was to monitor any nuclear explosion and report back to a central HQ. The shelters were equipped with a GZI (Ground Zero Indicator) and a BPI (Bomb Power Indicator)

The bunker at Winstone Beacon was manned from June 1959 to October 1968.

In 1959 the ‘Cold War’ was at its height, the government constructed a network of underground bunkers that were usually manned 24 hours a day by the ROC (Royal Observer Corp) with assistance from local reserve volunteers. Their purpose was to monitor any nuclear explosion and report back to a reginal HQ. The shelters were equipped with a GZI (Ground Zero Indicator) and a BPI (Bomb Power Indicator)

The bunker at Winstone Beacon was manned from June 1959 to October 1968.

In 2000 a survey was carried out which noted:-

All surface features remain intact with a two foot high concrete extension on top of the ventilation shaft adjacent to the access shaft. This is to raise the GZI because of the close proximity of the raised reservoir. The hatch is locked with an iron bar across the top and bolted to the sides. The bolts are removable. Internally there is evidence that somebody has been sleeping there recently with a sleeping bag and lots of candles and batteries. The table, shelf (detached), cupboard, twin bunks and a single bed remain. There is also a broken mirror, BPI mount (detached), siren crate and some GPO wiring and connection boxes.

During spring 2003 the above ground part of the access shaft was demolished and the shaft capped with a thick concrete slab.