Every day motorists on the A1 speed past Torness nuclear power station, a major landmark on the coastline of East Lothian.

Another much older landmark lies close-by, rarely noticed or even known about: Innerwick Castle.

The ruins of this ancient castle sit on top of a rocky promontory, overlooking the lovely wooded Thornton Glen through which Thornton Burn flows.

I was a child when I first saw this romantic ruin. It was 1971, I think, and I was staying at the nearby village of Innerwick with my primary-school classmates.

We slept in fold-down beds, went on nature walks and for the first time in my life I went pony trekking.

On the final morning of our stay we were taken to Thornton Glen and Innerwick Castle seemed to loom out of the imagination as we neared it.

Images of its crumbly walls, perched on top of a steep-sided cliff, remained with me many years afterwards. I didn’t know much about its story then, and to me it seemed like a fairy-tale ruin.

However, many years later I once again came across Innerwick Castle, but this time in the writings of an English soldier called Patten.

His tale of the castle’s destruction takes us back to the bloody days of the 1540s, when the Duke of Somerset had been sent to Scotland by Henry VIII to cause terror and destruction in an attempt to persuade the Scots to agree to the marriage of Mary Queen of Scots to Henry’s son Edward. It was to become known as the ‘Rough Wooing’.

The castle was then a stronghold of a branch of the Hamilton family. Across the other side of the glen there was another castle at Thornton. Both these castles were strategically important. The great north road ran by them, and they guarded the crossing of the burn at this point.

Today, the less romantically named A1 has blasted its way across the land, obliterating any sense of importance to landscape features. But in the 1540s, Innerwick and Thornton castles guarded the approach from the south at this point.

It was for this reason that Somerset surrounded the castles in 1548 and ordered their garrisons to surrender. It may now seem foolhardy, but the small garrisons in both castles refused to surrender. And so the drama began to unfold.

Master Hamilton, who was in charge of Innerwick, watched as a large group of hackbutters was positioned close to the castle. What was a hackbutter? Well, these guys had an early type of musket, often rested on a pole. Their aim was not brilliant, but sustained fire was quite terrifying, and the defenders of the castle had little defence against the whizzing musket balls, except to hide behind the battlements. And so under cover of this relentless fire, a group of hackbutters managed to break into the castle.

Let us imagine the panic of the defenders when they realised that these deadly attackers were now actually inside the castle! Huddled on the top battlements with swords and arrows, their arms were no real defence. They decided to appeal for mercy, and flew white banners, which was reported to Somerset, who sent a messenger to accept the surrender.

But meanwhile, inside the castle it was turning into a turkey shoot. The defenders were trapped in the upper battlements, and the hackbutters positioned themselves below with deadly effect. Musket balls were splitting through the flimsy wooden floorboards and flying through the air. Eight defenders were killed in this onslaught.

Then one of them took a decision. This is the man whose identity I would love to know. He must have stood staring at the burn below for a few moments before deciding to leap. It must have been a desperate moment. Hell had broken out in the castle and this was the only way to escape.

He hurtled himself into the air and then fell more than 70 feet into the shallow burn below. What thoughts flew through his mind as he careered towards possible death?

Then a crunch and an unbelievable gulp of breath as he found himself still alive! Yet he was not out of danger. The steep sides of the glen on each side were teeming with enemies. How to escape? The only way was to run along the course of the burn.

And so he picked himself up and began to run. The sound of gunfire and men yelling filled the glen, so the noise of his splashing sprint went unheard. His legs were powered by sheer terror and determination to survive. It was a truly remarkable feat!

And then, a hackbutter spotted him. It took just one shot to transform the scene. Our nameless hero fell in the water, his death witnessed by an unsympathetic Patten.

Soon, Innerwick Castle was ablaze.

Meanwhile, on the other side of the glen, Thornton Castle was also being attacked. Here we have a name of a man called Tom Trotter. He had been in charge of the garrison of 16 men, but had left the castle in a panic, locked the defenders inside, and taken the key!

He had left orders that the castle should be defended, and he promised to return the next day with help. But he never returned. The castle was destroyed by cannon fire, and most of the garrison killed. Those who survived were taken prisoner.

But what happened to this Tom Trotter? Was he a coward saving his own skin while leaving others trapped in Thornton Castle, or did he really seek help? If so, what happened to him?

To be honest, I can sympathise with him on the issue of the key. I mean, in the heat and stress of all that action forgetting to leave a spare key is kind of understandable, is it not? And he couldn’t really return the keys he had, could he? There were no letterboxes in castles in those days.

I think it is likely that Tom met his end on that day also.

Thornton Castle is now gone. But the ruins of Innerwick still stand on its rocky shelf, overlooking the Thornton burn. The day I stood by it as a child I had no idea of the drama of its demise, and the bravery, cruelty and tragedy of that day so many years ago.

I think it remains one of East Lothian’s lesser-known ruins because it remains hidden in its glen, even though it is also paradoxically so close to the modern icon of Torness.

I cannot visit the glen now without thinking about the man who leapt from the battlements and almost escaped by running along the burn, and of the fate of Tom Trotter.

And I can still see myself as a nine-year-old reluctantly leaving the glen at the end of a school trip that was in itself an adventure.