In recent years Cornwall has become a most unlikely route by which to conquer England. The distance from Continental ports is much greater than at say, Dover. Modern inventions such as aircraft and submarines would make the approach fraught with danger. Also, having seen the ridiculous little sunken roads of Cornwall I can say for certain that no modern army would wish to attack this inhospitable chunk of rock. I suspect that elderly Home Guards with pitch forks could keep a sizable foe at bay without much trouble.
But in earlier times it made sense for enemies, be they French or Spanish, to consider an attack. The fortunes of England depended on her command of the seas, and if you could occupy a few key ports along the Cornwall and Devon coasts you might challenge the Royal Navy's mastery.
On our walking tour in April and May we ran across many fortifications old and new.
This is St. Catherine's Castle overlooking the approach to Fowey. It is another "Device Fort" built by Henry in the 1530s. It is named not for Henry's last wife Catherine Parr (although I actually think all of his Queens deserve some kind of Sainthood for putting up with him), but for the point of land on which it stood. It was refurbished and rearmed to keep watch for a possible Napoleonic invasion fleet in the late 1700s. In 1855 a lower battery was added with a pair of 64 pounders. I am not sure exactly who they were expecting to defend against at that point in history.
I'd be surprised if a few bad jokes about St. Catherine did not originate from this design. Faintly visible on the far point is the expected fort on the opposite side of the harbor.
Falmouth is the most important port on the south Cornwall coast. So it is well defended. You see a mix of fortifications near the town proper, some old, some new.
This location has served for many centuries. The carved out arch is very old, the cement probably World War II. The odd arrangement that looks like a picnic table set up is some kind of range finding device.
On the opposite side of the bay we find a very well preserved coastal battery. It was built in 1880. Once again I am not sure who they thought they were guarding against at that point in history. Queen Victoria seemed to have the whole world running smoothly back then.
I found it rather charming that the aiming marks for this six inch gun were scratched into the cement.
At some sites you find all different eras of lookout stations.
This is on a point of land called "The Gribbon". Iron age folk lived here. From this spot the Spanish Armada was sighted and a warning beacon was lit. Later a signal station was build to watch out for Bonaparte. Exactly which of these eras is recalled in the above remains is difficult to say.