Summary:
Hurst Castle is a coastal artillery fortress built by Henry VIII in the 1540s as part of his chain of Device Forts—emergency coastal defences constructed amid fear of European invasion. Sitting dramatically at the end of a shingle spit in Hampshire, it has guarded the western approach to the Solent and the naval port of Portsmouth for centuries. But its role didn’t stop with the Tudors. It became a prison for Charles I, a Victorian-era garrison, and even a World War II anti-aircraft post. This long, linear structure is a fascinating case study of how English defences were reworked and repurposed across five centuries.
One more off the list!
I visited this area during the first year of my project with the intention of visiting Hurst Castle. Stupidly, at the time, I hadn’t quite mastered the art of planning ahead when it came to vanlife. Ironic given I was a brilliant IT Project Manager.
Had I, like I do since, done some research I would have known before booking a campsite in the area, that the castle was indeed closed due to substantial damage (more on that below) and closed to the public.
So I spent my time enjoying what was Winter (Jan/Feb ’22) exploring Lymington and the surrounding marshes.
Having researched it this time, I have booked into a campsite and had hoped to see the castle and a few other sites in the area whilst here. Sadly, the weather is not great for the entire 7 days I am here. High winds daily with rain predicted for 6 of the 7 days.
Today, 4th June ’25 is the only clear day during my stay! So Hurst Castle was my priority site to visit so its where I headed.
If you’ve followed me for any length of time on any of my socials, you may know that I’m not one for heights. But today I did manage to get a few flights up which I then immediately regretted when a gust of wind would almost knock me off my feet!
There was one stairwell that I simply didn’t like the look of. If I can see through the steps, my body says no. But I’m pushing myself as much as I feel comfortable doing being on my own.
Visiting castles are a project within the overall programme that is my photography project. Cathedrals, historical buildings and ruins and ancient sites being some others. I’m just fascinated with history in my adulthood (I don’t remember being that keen in my youth / school years) and learning about all these sites and then researching the names behind it I’m finding very interesting. I definitely know more about the history of the UK than I do of my homeland of South Africa. Something I do hope I have the opportunity to correct before my time is up.
I opted to take the ferry from Keyhaven to Hurst Castle. It costs £5 per adult one way or £8 return (apologies, I didn’t note the other prices). The other option is a 1.5 mile walk (each way) along the shingle spit. Which, before I was in my biking gear, I didn’t fancy. Also, the ferry provided a different perspective winding its way through the moored boats.
Both the boat and the castle is dog friendly. With many dogs making their journey over by ferry with their humans.
Let’s get into the history stuff 😊
Historical Context: Why Was Hurst Castle Built?
Let’s take you back to the early 1540s. Henry VIII, having divorced Catherine of Aragon and broken with the Catholic Church, had pissed off just about everyone in Europe. France and the Holy Roman Empire were suddenly best mates again and seriously considering invading England to dethrone the religious rogue monarch.
This meant Henry had to shore up his south coast. Enter the Device Forts—a network of artillery castles built at key coastal locations. Hurst Castle was constructed between 1541 and 1544, strategically located to guard the western entrance to the Solent, the waterway leading to Portsmouth and the naval dockyards.
Its position was perfect: perched on Hurst Spit, a 1.5-mile natural shingle bank jutting into the Solent, it could fire on enemy ships approaching from both the Isle of Wight side and the mainland. The castle formed part of a triangulated defence system along with Calshot Castle and Yarmouth Castle.
Original Tudor Design (1540s)
The original structure of Hurst Castle was a central circular keep surrounded by a ring of thick stone walls with gun embrasures (openings for cannons). This layout allowed for 360-degree artillery fire—cutting edge stuff at the time.
It’s one of the more advanced of Henry’s Device Forts, incorporating:
- A central keep with two storeys and rooftop gun positions
- A low, circular curtain wall with 26 gun embrasures
- A moat (now mostly filled in) separating the inner keep from the outer wall
- Barrack rooms and powder magazines housed within the walls
It was designed purely for defensive gunfire, not as a residence or high-status castle. You weren’t meant to live in it, just defend the realm from it.
Charles I’s Imprisonment at Hurst Castle (1648)
Hurst Castle earned a brief but grim place in the annals of English royal history as one of the final prisons of King Charles I. By late 1648, during the second English Civil War, Parliament had firmly regained control, and Charles, already defeated once, was recaptured after continuing secret negotiations with the Scots.
He arrived at Hurst Castle on 1 December 1648, under heavy guard. At that time, the castle was in poor condition—barely garrisoned, structurally neglected, and isolated on the windswept Hampshire coast. His jailer, Colonel Richard Harrison, had to scramble to make the place secure enough to hold the King.
Charles was detained there for 19 days, with most reports suggesting his living quarters were sparse and the weather was bitter. The castle was seen as remote enough to prevent any rescue attempts, but close enough to Portsmouth to arrange for his transfer without delay.
On 19 December 1648, Charles was taken by boat from Hurst Castle to Cowes on the Isle of Wight, and then by ship to Southampton and onwards to Windsor Castle. From Windsor, he was moved to St James’s Palace in London, where he was held prior to trial.
He was tried by a specially convened High Court of Justice beginning on 20 January 1649 at Westminster Hall. Despite his refusal to recognise the legitimacy of the court, he was found guilty of high treason.
On 30 January 1649, Charles I was executed outside the Banqueting House in Whitehall, London. His stay at Hurst Castle was a brief but pivotal step in his journey to the scaffold, making the fortress forever associated with one of the most seismic events in British constitutional history.
The Victorian Expansion (1850s–1870s)
By the 19th century, Britain’s military thinking had changed. The fear now wasn’t galleons but ironclads—heavily armoured steam-powered warships.
The castle was massively rebuilt and extended during the Palmerston Forts programme—a nationwide fortification scheme named after then Prime Minister Lord Palmerston, who thought the French were getting twitchy again.
Key changes:
- Two massive wing batteries were added to either side of the original Tudor keep
- Thick granite and concrete gun casemates were installed, housing 38-ton rifled muzzle-loading (RML) guns
- Ammunition storage, troop quarters, and workshops were built into the wings
- An underground tunnel system linked parts of the fort
These wings are what give Hurst Castle its long, linear appearance today. They stretch the whole width of the shingle spit, making it one of the longest artillery castles in Britain.
The 38-Ton Guns: Victorian Muscle in a Brick Overcoat
By the mid-19th century, it became painfully obvious that Henry VIII’s original castle — impressive though it once was — wouldn’t last five minutes against the sort of high-powered artillery now sailing the seas on steamships. Britain’s enemies weren’t turning up in wooden ships with a few cannonballs anymore. They were developing ironclads: warships plated with metal and armed to the teeth.
So, what did the British government do? They went full arms race and ordered massive rifled muzzle-loading guns (RMLs) to be mounted in newly built casemates at coastal forts like Hurst Castle. And I do mean massive.
What the Hell Is a 38-Ton Gun?
The clue’s in the name: these were 38-tonne beasts of cast iron and steel, officially designated as 12.5-inch RML guns. The “12.5-inch” refers to the internal diameter of the barrel — that’s roughly the size of a dinner plate — and yes, they did actually fire projectiles the size of small barrels.
Each gun was capable of firing a 820-pound (372 kg) shell a distance of over 7,000 yards (6.5 km). That’s nearly four and a half miles — far enough to ruin any enemy captain’s day well before they even saw the castle through their spyglass.
The Engineering: How They Worked
These guns were muzzle-loaders, meaning you had to stuff all the gunpowder, wad, and shell in from the front of the barrel — a laborious and frankly dangerous process considering the size of the thing. Victorian engineers, to their credit, managed to speed up the process with specialised loading rails and hydraulic traversing gear, but firing one still took a full team of trained gunners and several minutes per shot.
The barrels were rifled, which means they had spiral grooves inside that spun the projectile, increasing accuracy and range — a vast improvement on the smoothbore cannons of the Napoleonic era.
Each gun sat inside a casemate — a heavily armoured gun chamber with a small opening facing the sea. Behind the gun were thick brick vaults and metal tracks to help shift the barrel side to side (called “traversing”) and elevate it for distance.
Installation at Hurst Castle
Between 1861 and 1874, the British War Office rebuilt Hurst Castle with new east and west wing batteries, each housing several casemates with these 38-ton RMLs. The construction was part of a nationwide effort driven by Lord Palmerston’s fear of French invasion — hence why this period of fort building is known as the Palmerston Forts programme.
At Hurst:
- Each wing battery housed 11 heavy gun positions, many of which were fitted with 12.5-inch or 9-inch RMLs.
- Ammunition was stored in underground magazines, with hoists used to bring powder and shells up to loading height.
- Loading drills were practised obsessively — it could take up to 10 minutes to reload after each firing.
The castle’s design meant these guns could sweep the entire Solent, guarding the western entrance alongside the guns at Fort Albert and Fort Victoria on the Isle of Wight.
Problems and Limitations
As formidable as they looked, the 38-ton RMLs were already on the way out by the time the final ones were installed. Why?
- Too Slow: Loading from the muzzle was painfully inefficient compared to breech-loading guns, which were already being used by navies.
- Vulnerability: Once a gun fired, it had to recoil back into the casemate, be sponged, reloaded, and rolled forward again — all while under fire.
- Labour Intensive: Each gun required a team of up to 9–12 men, trained to precision, in a space hotter than a Victorian foundry in summer.
By the 1890s, most of these guns were obsolete, outmatched by more modern breech-loaders with faster firing rates and greater range.
Survivors and Legacy
Several of Hurst Castle’s 38-ton RML guns still exist in situ today, although not all are in their original working condition. If you visit, you’ll be able to:
- See the massive iron carriages still sitting on their original traversing rails.
- Peer down the barrels (if you’re allowed — check with the staff).
- Stand beside them and wonder how on earth they were ever installed without modern cranes. (Answer: block-and-tackle systems, blood, and probably a lot of swearing.)
Hurst is one of the very few UK fortifications where you can still see these guns in their original casemates, giving a real sense of scale, engineering ambition, and military paranoia.
Pub Quiz Bonus Facts About the 38-Ton Guns
✅ The guns were obsolete within 30 years of installation — a classic case of Victorian over-engineering meeting rapid technological change.
✅ The guns were made by the Royal Gun Factory at Woolwich and later by Armstrong Whitworth.
✅ They used up to 112 pounds of black powder per shot.
✅ Their maximum range was about 7,200 yards, depending on elevation.
✅ They were never fired in anger from Hurst Castle — but plenty of test firings occurred.
World War II Defences
As if this place hadn’t done enough, it had another outing during World War II. The castle was rearmed to combat the threat of German invasion and air attacks.
Updates included:
- Quick-firing anti-aircraft guns
- Radar installations (some remnants remain)
- Reinforced machine gun posts
- Barracks and command posts for coastal artillery crews
The Victorian gun emplacements were too slow for modern warfare by this point, but the position remained vital for coastal defence and observation. It was manned throughout the war and only decommissioned in the 1950s.
Present Day: Collapse, Preservation and Controversy
Hurst Castle has been under the care of English Heritage since 1983. It is open to the public, and you can either walk the shingle spit (about 1.5 miles) or get there by a charming ferry from Keyhaven.
But the site is now a poster child for climate change, coastal erosion, and the headache that is heritage conservation.
In February 2021, a large section of the eastern wing collapsed into the sea. Years of erosion had weakened the sea defences. The 19th-century walls had been undercut by rising tides and storms. It was a big wake-up call about the vulnerability of our coastal heritage.
Restoration work is ongoing, with a combination of coastal reinforcement and structural repairs being debated. But it’s a costly and complicated effort.
Things to look out for during your visit:
Visiting the Garrison Theatre
The Garrison Theatre is accessible to the public as part of the Hurst Castle experience. It offers a poignant glimpse into the lives of soldiers stationed at the castle during World War II and stands as a testament to the enduring power of performance and camaraderie in challenging times.
Twin-6-pounder guns
In a place best known for giant Tudor cannons and 38-ton Victorian monsters, the twin 6-pounder might look like the new kid in school trying not to get wedged. But don’t be fooled — it’s fast, accurate, and the only gun at Hurst that could realistically stop something small and fast from dashing past the Solent defences.
It represents a turning point in military engineering: a shift from brute force to speed and efficiency. While the big guns were still great for a show of strength, these nimble twins were the ones likely to do the actual work when the alarm sounded.
Notable Features
- Gun Platforms and Casemates: Walk the length of the Victorian wings and see the original gun platforms with their iron tracks.
- Central Tudor Keep: One of the most complete Tudor artillery towers in England.
- WWII Features: Machine gun posts, command positions and remnants of radar gear.
- The Shingle Spit Walk: A truly unique approach to a fortress, surrounded by sea on both sides.
- Views: Spectacular views of the Isle of Wight, The Needles, and the Solent.
Glossary of Terms
- Device Forts: Fortifications built on Henry VIII’s orders to defend against foreign invasion after he split from the Catholic Church.
- Gun Embrasure: An opening in a wall designed to fire cannons or guns through, offering maximum range with minimal exposure.
- Casemate: An armoured room in a fort where a gun is mounted.
- Palmerston Forts: A series of defensive forts built in the Victorian era due to fears of French invasion under Napoleon III.
- RML Gun: Rifled muzzle-loading gun; used from the mid-19th century before breech-loaders became the standard.
- Shingle Spit: A narrow bank of pebbles or gravel formed by longshore drift, often separating a lagoon from the sea.
Pub Quiz Gold: Quick Facts
- Built by: Henry VIII, around 1541–1544.
- Prisoner Held: Charles I stayed here before his trial and execution in 1648.
- Victorian Expansion: New gun batteries added in the 1860s–70s with cutting-edge rifled guns.
- World War II Use: Rearmed for anti-aircraft and coastal defence.
- Collapse: In 2021, part of the east wing collapsed into the sea due to erosion.
- Managed by: English Heritage.
- Access: On foot along Hurst Spit or via ferry from Keyhaven.
- Fun Fact: It’s longer than any other Device Fort and one of the few still bearing visible marks of all its military eras.
Final Thoughts
Hurst Castle is more than just a ruin by the sea—it’s a layered narrative in stone and shingle. From a Tudor panic-project to a Victorian muscle flex and a WWII radar station, it encapsulates centuries of England’s defensive paranoia. And now? It’s a battleground for conservationists trying to save it from the same sea it was built to watch.
Whether you’re after history, a unique walk, or an unbeatable coastal view, Hurst Castle delivers. Just don’t forget your walking boots—or the tide times.
