On the Tower hill in Gourock, next to the new football fields, there is a structure that many of us will have seen at some point or another but how many of us know what it actually is, or what it was used for? The small surface structure is actually an entrance into an underground bunker that was used during the “cold war” by the Royal Observer Corps (ROC).
ROC posts are small underground bunkers that would have been used in the event of a nuclear strike on the country. They were designed to monitor the location, altitude and fallout generated by a nuclear explosion. In total there were over 1000 ROC posts built and this extensive network would have enabled the Department of Civil Defence to gain valuable data about any nuclear attack on the UK.
The above images show the entrance shaft that would lead down into the “bunker”. The shaft is 14 feet deep and accessible by a ladder secured to the wall of the shaft. There is also a secondary shaft that provided air flow and ventilation.
ROC posts were not manned constantly. Only when they was a real threat of a nuclear strike would the ROC volunteers be given their order to “man the post”. In the event of a nuclear strike on the country the post crew would be expected to remain in the bunker for up to three weeks. The post crew was 3 persons.
Prior to the cold war
The ROC were in existence long before the cold war. They were originally called the “Observer Corps” before being officially recognised in 1941 and receiving the addition of “Royal” to their title. The Origins of the ROC can be traced right back to the Napoleonic wars where they would light beacons to alert the population of possible warships approaching the shores.
The outbreak of WWII provided the ROC with a new role. Volunteers would be enlisted to identify aircraft. By being able to identify aircraft in flight and relaying this information to the area command, it was much easier to identify an aircraft as friend or foe.
Aircraft Monitoring
Very often when you visit the location of an ROC post you will also see the remains of the aircraft monitoring post. This was usually a small pre-cast concrete structure called an “Orlit post”. It contained a small sheltered room with a door leading to an observation deck. There was also a variation of this design with the entire structure set on stilts. This was called an “Orlit B”.
Neither of these structures can be found on the Tower Hill, so did it simply not have one?
The location of the cold war nuclear monitoring post was generally next to the aircraft monitoring post for two main reasons. The location was suitable for both purposes and they already had volunteers in the area. There are also reports of the ROC using exiting structures to act as aircraft monitoring posts.
There has always been a story about a possible lookout point being positioned on top of the tower but no real information about it’s use. It could have been related to monitoring the Clyde as part of the “Clyde Royal Garrison Artillery” who were responsible for the “Clyde Boom” or part of the Tower Hill Anti-Aircraft battery.
Aircraft Monitoring Post
It is very likely that the structure on top of the tower was the shelter for the ROC aircraft monitoring volunteers. The rest of the tower top area would have been used for monitoring. There would have been optical height/range finders and possibly even compass headings drawn on the inner walls.
It is interesting to note that no part of the structure is visible from ground level and with the Tower being the highest point in Gourock, it is unlikely the building would have been seen. The metal hooks set into thee stonework are the only visible clue that there is something up there. The hooks were probably used to support a ladder to allow the crew access to the top.
The ROC played an important role towards the end of the second world war and into the cold war. Thankfully there were never put to the test in their nuclear monitoring capacity. It is important to locate and document unusual styles of monitoring posts like the one found on top of the Tower hill, because eventually they will be lost and forgotten about.
The ROC was stood down in 1995.