Castles and fortresses are all about keeping others out. Like the razor wired army camps of the present day, these places were designed to be as inaccessible and impenetrable as humanly possible. 'Come near and we will annihilate you!' And they did.
If you pay English Heritage a 'small fee' you will be able to clamber up the hill to Pendennis Castle and find cannons pointing in all directions, ready to take out anyone with a string on onions. Why onions? Well, this was originally King Henry VIII's fortress (xenophobic heavyweight as he was) and that dude wasn't about to let just anyone waltz in. Later, when Henry had succumbed to just one too many McDs, anyone foolish enough to arrive on the horizon wearing a sombrero was looking down the same set of loaded barrels. Then of course there was an insane civil war to bring a bit more blood and carnage to the site, and then the whole Second World War thing.. and so it goes on and on. Human beings can't stop fighting for long and love to chew it over.
What this castle, and all such erections say to me is "I'm right and you are wrong!" Here I stand, no one can miss me, I'm a stone built expression of intransigence and I will not be moved!
And this one hasn't been, not for 100s of years. It stays there and reminds us of our violent past.
Now we are looking at a new generation of invaders - refugees this time, displaced people, homeless, desperate and in need. If we should believe the popular press, they are as bad as any onion or sombrero wearing attacker. With such voices as Katie Hopkins given so much publicity, perhaps the cannons will be turned on to them too.
Last year I went up to Pendennis with my grandchildren. It was summer and a lovely warm day. In the gun room a tape was playing with sound effects of gunfire and people shouting. There was fake smoke and the sounds of battle. All good fun for the kids, eh? Some of the holes in the walls had glass in them, and in those windows were dozens of butterflies. Every time the noises went off and the smoke belched out, they fluttered in alarm, unable to get out they were exhausting themselves. It went on and on... and it actually made me feel sick.
Isn't this typical of us though? We are so selfish. Our actions impact on this world in more ways than we can know, even when we are only pretending to kill each other.
Perhaps instead we could look to the castles as reminders that we don't need to be right all the time. These places saw so much death and suffering, and surely one day we will have had enough of all that. Perhaps, as we evolve - which we surely must - we will see castles as the relics of our violent ancestry, something that we are only too pleased to leave behind.
I reported the plight of the butterflies to the castle office, and to give English Heritage their credit, the young lady seemed genuinely concerned and promised to get them released. I hope she didn't forget.