The archaeological dig looking for a hidden piece of history at Corfe Castle in Dorset, is to feature in a BBC TV hour-long prime time programme.
Hidden Treasures of the National Trust, screening at 9 pm on BBC2 on Friday 6th June 2025, tells the story of Lady Mary Bankes, the last custodian of Corfe Castle before it was ruined in 1646 and also hunts for a long lost historic gate or sallyport.
Corfe Castle has been in ruins since 1646, after the English Civil War, but still hides many secrets
Time to solve a 400 year old mystery
The long lost sallyport – a secretive way in and out of the castle – eventually led to the castle’s downfall when a traitor let the besiegers in to end a second siege.
Archaeologist Martin Papworth spotted an archway when he began his career at Corfe Castle in 1986, which he now believes could be the upper entrance to the hidden sallyport.
He made it his last job before retirement to prove that it was beyond doubt the way that traitors allowed the castle to fall to the Parliamentarians – and BBC cameras were there to record his attempt.
Historic England allowed special permission for two days of excavation under strict conditions at Corfe Castle in summer 2024 and the archaeological team was sure that gave them enough time to solve a 400 year old mystery.
Visitor experience manager Eoin McDowell at the site believed to be the downfall of Corfe Castle
“Heroic defence of castle in 1643”
Corfe Castle visitor experience manager, Eoin McDowell said:
“It’s really exciting to be part of the BBC programme. Corfe Castle was owned by the Bankes family at the time and they were staunch Royalists and huge landowners, a very wealthy, powerful family.
“Lord John Bankes was Attorney General to King Charles I and when the Civil War broke out he went off to fight for the Royalist cause.
“During the Civil War there were two sieges of Corfe Castle, the last stronghold of the Royalist cause in Dorset, and for the first of them while her husband was away fighting, Mary Bankes was at Corfe and responsible for running the defence of the castle.
“Over the years there has been quite a narrative that she was here for the second siege as well, but there is documentation that she was at Cambridge then. However, she has become synonymous with the heroic defence of the castle in 1643.”
Finds made during the dig to excavate Traitors Gate, included glass from a Tudor window and painted plaster from the walls
“Saw the writing on the wall”
Eoin added:
“We know who was responsible for letting the enemy into the castle during the second siege, Sir Colonel Pitman, who saw the writing on the wall. The siege had been going for six months, there were less than 100 men in the castle defending it, and winter had set in.
“He left the castle saying he was intending to bring back some Royalist reinforcements, and instead he brought back Parliamentarian soldiers, who very quickly took the castle within minutes with just a small amount of fighting.
“Then after the Civil War, Oliver Cromwell ordered that Corfe Castle should be destroyed, because it was the last remaining Royalist stronghold in Dorset and they didn’t want it to be a beacon for Royalism.
“They used a lot of gunpowder to blow it up from the inside and levied a tax on local citizens to pay for it, which was particularly mean!”
Kate Bethune with a statue honouring Lady Mary Bankes, at Kingston Lacy in Dorset
Lady Mary Bankes, the last custodian of Corfe Castle, who held off a siege by Parliamentarian soldiers in 1643
“Daughters and servants joined the defence”
Kate Bethune, cultural heritage curator for the National Trust, said:
“The Civil War impacted people across all levels of society and women were often key players in what was happening – they had to keep things going while the men were away, they had to run the household, they had to hold the line and hold the fort.
“We see Mary as this strong, formidable woman defending the castle during the first siege. Some sources say that she started with just a handful of soldiers, facing hundreds of Parliamentarian troops at the gates, and that her daughters and servants joined the defence.
“A bronze relief was later commissioned which showed women hurling embers and boulders down on the advancing troops, and Mary herself portrayed above the outer gatehouse holding a sword.
“Legend has it that the Parliamentarians gave her back the keys to the castle in tribute to her bravery. It would be wonderful if we could discover the sallyport, as it was such a critical moment of huge drama in the castle’s history, and to be able to pinpoint that with accuracy would be really exciting.”
National Trust archaeologist Martin Papworth on his final dig at Corfe Castle
Finding three lost mansions
Martin Papworth retired in 2024 after 38 years with the National Trust as their Wessex archaeologist.
His career included the discovery of a Roman temple and town at Kingston Lacy near Wimborne, unveiling a medieval hunting lodge, dating the Cerne Abbas Giant in mid Dorset, and finding three lost mansions and an ancient mosaic at Chedworth Roman Villa in Gloucestershire.
But he wanted his final mission to be a definitive confirmation that the archway he’d spotted early in his career was indeed the point at which the fate of Corfe Castle was sealed.
Martin Papworth and his team had just two days to find and excavate the long lost sallyport of Corfe Castle
“In 1992, I found a clue”
Martin Papworth said:
“We have documents to tell us that when the castle was captured, the Parliamentarian soldiers didn’t come through the main gate, but through a sallyport, a small gateway that allowed troops to come and go discreetly.
“I’ve been coming here to Corfe Castle for at least 38 years now, my first ever job for the National Trust was here back in 1986 and this was my last before retiring.
“In 1992, I found a clue that might point to the lost sallyport, the very top of an archway. It wasn’t our job to do anything about it at that time, so it was left as a mystery, but I have never lost that sense of excitement in archaeology.
“If we found a gateway where I remember the arch, we would also need to show where it came out at the bottom of the castle walls to verify our theory.”
Martin and his team were determined to solve the mystery
Hoping that the Inner Ward of Corfe Castle will give up its secrets
“Corfe is giving up secrets slowly”
Martin added:
“The sallyport is fundamental to the history of Corfe Castle, the capture of Corfe by the enemy troops tricking their way through this entrance, enabled Parliament to order its demolition. Today’s much-loved ruin is the direct result of this action.
“Letters from the time describe Parliamentarians quickly getting control of the Inner Ward which made us suspect there was a sallyport high in the castle. This arch within the Inner Ward seemed an obvious place to explore.”
“Only the top section of the gateway was revealed during this dig. The floor of the sallyport is likely to lie a further 1.5 metres below the 1640s rubble and these deeper areas could hold more answers or clues. Corfe is known for giving up her secrets slowly.”
James Gould, operations manager of Corfe Castle, features in the BBC2 show
Further information
- The outcome of the dig is revealed on BBC 2’s Hidden Treasures of the National Trust Series 3, episode 4, Women on the Frontline, broadcast on Friday 6th June 2025 and also available on iPlayer
- Check out all the events at Corfe Castle on the National Trust website
