Rescuing a Fallen Giant: Tower at Corfe Castle Stabilised After 800 Years
A fallen guard tower at Corfe, sitting at a 35-degree angle over a 30-metre-deep valley at has been successfully conserved
A fallen tower at Corfe Castle, sitting precariously over the mound has been successfully conserved.
The guard tower, built during the reign of King John (1199-1216), was destroyed by parliamentarians in 1646 and fell, embedded at a 35-degree angle over the mound at Corfe Castle where it has stayed. Access to this area is one of the most difficult due to its angle and overhang to the valley below but was gained by a specialist team as part of the current comprehensive £2 million, three-year conservation project at the castle.
Expert stone masons working for the National Trust are conserving areas of the castle, removing vegetation to prevent future damage. The work, which will see repairs on nine towers, the Keep and the eight-metre-high (26 feet) curtain wall, will continue throughout the seasons and is due to finish in early 2026.
Impact of Climate Change on Corfe Castle
Corfe Castle undergoes regular structural condition surveys and is structurally stable. However, the impact of climate change with warmer, wetter winters accelerates growth of vegetation, such as valerian which grows its roots deep into the core of the walls. Hotter summers sees the vegetation die off leaving gaps which dries out the mortar joints.
The walls of the castle were built early in the 13th century by highly skilled stone masons with 2-3-metre-thick walls made up of two layers of facing stones, known as ashlar, sandwiching a core of rubble, all held together with lime mortar. This construction gives the walls incredible strength – unless you blow them up and expose them to the UK weather!
The ivy growing within the walls of this tower had pushed stones and sections out of line, so conservators needed to build a scaffold to create a level walkway 30 metres above the valley below and a bespoke frame to lift away stones each weighing between 50-90kgs, before clearing the area and placing them carefully back into their original place.
Russell Coombe, Project manager from Stonewest, specialist stone masons working to conserve the castle, said “This has been the most challenging section of the castle to date. Not just because of the work needed, the precarious angle and drop to the valley below but the weight of each stone at 50-90kgs was challenging”. They continued, “We had to work with strength but absolute precision. It was phenomenal to see the work of the 13th century stone masons up close– such craftmanship”.
Conservation at Corfe Castle
- Specialist conservators undertook a formidable task to heave stones weighing up to 90kgs over the valley to clear vegetation before resetting
- First time stones had been handled since early in the 13th century and unusual markings give us a glimpse of the working practices at the time.
- The work is essential as Corfe Castle is threatened by more extreme weather.
- A £2 million, three-year conservation project is in its second full year and a campaign to raise £100,000 is ongoing.
Shining a light on Corfe's original stone masons
Stone masons’ marks found carved into the stones during previous conservation work included markings around arrow slits to ensure the stones were positioned correctly and various symbols which were thought to be tally marks to show employers how much stone had been worked on during a day. The masons’ marks on stones of the fallen guard tower are different again and include simple scratch marks. The variety of widths and depths suggest they were made by a few different masons, but their purpose is a mystery.
Also identified were the marks of a stone mason’s axe, a well-known early technique to shape the stone and ‘pit’ marks made by a chisel to position pinchers to lift each stone into place. This method of lifting heavy stones is still used today.
Corfe Castle - 11th Century to English Civil War
Parts of Corfe Castle date to the 11th Century when it was a royal castle and an important stronghold. In private hands from the 16th century, it became the family home of the Bankes family in 1635.
During the Civil War, the Bankes supported Charles I and, while her husband was serving the King, Lady Mary Bankes led the defence of Corfe Castle during two sieges.
In 1645, during the second siege, many defenders of the castle were not locals but regular troops with less loyalty to the Bankes family. One of the officers, Lieutenant Colonel Pitman, treacherously let enemy soldiers through a side gate (or sallyport) and Corfe Castle was captured.
An act of parliament was passed in Wareham calling for the demolition of the castle and the castle walls were undermined. Gunpowder was used to destroy it, leaving the romantic ruins we see today.
Challenges for conservation of Corfe
The castle was built in different phases and repairs at different times have brought challenges for the project team. Several different types of mortar are used, and the conservation teams have developed recipe books for their own mortar mixes so they can mimic the originals.
As well as replacing mortar, the exposed wall tops are protected with a technique called ‘soft capping’ by covering exposed wall tops and tumbles with grass as a natural but incredibly effective way to protect against extreme weather. The grass prevents too much water from getting into the rubble core of the wall where it washes out material and attracts unwanted plants to grow into the walls.
The National Trust conservation teams work with ecologists to ensure nature living on the castle don’t have their homes disturbed. The stones are not cleaned to protect important lichens which are carefully left alone, as are nesting birds including ravens and the Peregrine falcons which build homes high in the ruins of the castle. The conservation teams even have to be mindful of adders and lizards found living among the ruins.
King's Tower and Fundraising Appeal
Conservation of the castle is costing £2 million over three years and is being supported with a generous grant of £150,000 from the Wolfson Foundation as well as a commitment from the National Trust’s own funds. There is still a need to raise £100,000 to ensure the project can be completed.
James Gould, Operations Manager at Corfe Castle said, “Work continues to ensure Corfe Castle stands proud for future generations”. He continued, “Every time you visit, book a tour of the Kings’ View or donate to our conservation work, you support the effort”.
A fund-raising appeal is ongoing, and Historic England has allowed a platform to be built high within the Keep of the castle to provide a unique visitor experience to help raise funds. Called the Kings’ View, visitors can experience unparalleled access to areas once restricted to royalty.
On a tour of the Kings’ View, visitors can enter the area that was once royal living quarters and get close-up access to rare historical features and panoramic views from near the top of the castle. The platform will be open while conservation works continue and a full 90-minute tour of the castle culminating with the Kings’ View is bookable via the Corfe Castle website or short 30-minute tours of the Kings’ View are bookable on the day. All proceeds from the tours go directly towards the conservation works.
