Hush-Hush, Knockarnahan
This site is known locally as “Hush-Hush” and said to be a WWII radar station.
It is located South of Portpatrick at NX 0199 5299.
There is no record of a RAF radar station there and it does not fit with any standard style of building.
One large building 17.3M x 7.5M and a smaller one (possibly MT shed? or engine house though no exhaust seen).
The large building has is aligned so the long side faces 186 degree magnetic - not parallel to the road.
The large building has two large doors and large windows at the West end of the South side.
There are two concrete(?) “lumps” on the roof though these might be covering square holes in the roof that can be seen in the ceiling when photographed through the open window.
No tower base seen just a few lumps of concrete South of the building.
Microwave tests were done between various sites around the Irish Sea between 1942 and 1946. One path was Fishguard to Portpatrick. One Portpatrick site was at 93ft OD, that could fit with somewhere near the GPO radio station. The other was at 375ft OD at Knockharnahan which would seem to be this site as that is the name of the area and the site is about that height above sea level.
It is said the 4ft dishes were mounted behind hessian “windows” which could explain the large windows at one end of the building.
Or possibly the large door in the South side of the building could have been where a dish had been.
“The Portpatrick 9cm receiver started working at the end of August 1943 but did not receive any signals until March 1944, shortly before the installation of the higher station” - i.e. this one. “On 3cm all stations were operational by July 1944”.
Information from Wings Across the Border ISBN 1-84494-010-1