Geophysical survey of Kilmacahill deserted settlement complex, County Westmeath: project aims and goals

Vicky McAlister, project lead of the Geophysical Survey of Kilmachill explains the reasons behind the survey.

“Can we use drone (UAV) gathered imagery to see how spaces around castles were being used?” This was the question that spurred the addition of geophysical survey to a wider study of the landscape surrounding the deserted medieval settlement complex at Kilmacahill, County Westmeath. The data will then be delivered to the Human-Environmental Exchanges in the Landscape (HELM) project team for analysis to detect possible subsurface archaeological remains. HELM is led by project co-Principal Investigators Dr. Vicky McAlister and Dr. Jenny Immich, with Target Archaeological Geophysical GVC commissioned to undertake the survey.

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Kilmacahill was selected for this interrogation because of its layered landscape history and good above surface archaeological remains. The vernacular settlement site of Kilmacahill is adjacent to a Franciscan Third Order Regular monastery and within visual range (c. 1km) of Joanstown motte and bailey, located to the west of the site. The work at Kilmacahill already undertaken includes UAV collected aerial photographs and topographic data over the deserted settlement complex for analysis in geographic information systems (GIS) software.

Geophysical Area 1

In its first project phase (2019-2021) HELM addressed the theory that Anglo-Norman medieval vernacular settlements could be found in close physical proximity to elite secular and religious sites. More specifically, we hypothesised that peasant settlement could be found clustered around castle sites, parish churches, and monastic sites. To test this theory, HELM analysed UAV-gathered data for four castle sites in counties Limerick and Tipperary. At three of these four sites we found what we interpreted to be burgage plots clustered in the area between the castle and parish church. One of them, Glenogra in County Limerick, looked to have a deserted medieval village showing different areas and types of house plot compared to the very planned and regular appearance of such plots at the other sites. We wondered if this indicated that both Anglo-Norman settlers and Gaelic Irish tenants were living in this settlement.

Geophysical Area 2

This led the HELM team to begin phase two of the study, which is looking at three potential deserted medieval settlement sites in County Westmeath: Fore, Kilbixy, and Kilmacahill. Westmeath was the contact zone or frontier between the Anglo-Normans and Gaelic Irish for an extended period of time. This duration made us interested in what the medieval settlements associated with castles there looked like morphologically: more like Glenogra and haphazard, or something else entirely?

In late 2021, thanks to funding from the American Philosophical Society, Dr. Paul Naessens of Western Aerial Survey collected data from UAV flights at these three sites. At one of them – Kilmacahill – he also tested a new addition to the arsenal of digital archaeologists: UAV-mounted multispectral cameras. Multispectral data is traditionally used by scientists as an effective tool to examine soil productivity and plant health. In archaeological contexts, multispectral imagery can be analysed to reflect relative differences in vegetation health as a proxy to indicate near-surface or subsurface anthropogenic features – such as field boundaries made of stone, pits with charcoal in them, crushed gravel pathways, or other architectural features. The vegetation above these man-made features appears not as healthy as that above natural ground in the data analysis. The UAV-gathered photogrammetry data showed some interesting house plots, but also details of a complex circular enclosure not listed on the Sites and Monuments Record.

Geophysical Area 3

The HELM team agreed that concentrating our resources on one site would help to test our methodology and thus we applied to the Castle Studies Trust for funding for geophysical survey. We hope that the combination of three methods will tell us the most about vernacular settlement located between the Franciscan house at Kilmacahill and the motte castle at Joanstown. We will also be able to test the robustness of our UAV-based methodology against geophysics, which is much more expensive but is standard practice for identifying low-lying archaeological features. Geophysics currently costs up to ten times the amount of flying a site with a drone, so if we are successful in using UAV data to identify castle features, then this will be good news for everyone seeking to know what’s going on around their sites!

The data produced by the three collection methods (UAV photogrammetry, multispectral, geophysics) will be incorporated in GIS software to create a visual of the immediate subsurface archaeological remains of the DMV and will uncover finer features of the site as a whole. The HELM team should have the exciting results of the surveyed area by Autumn 2022.

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Revealing the hidden stories of Pontefract Castle

Ian Downes from Wakefield Council looks at the geophysical survey being carried out week commencing 9 May 2022 on parts of Pontefract Castle yet to be explored archaeologically. The work, funded by the Trust is being carried out by Wessex Archaeology.

Pontefract Castle in West Yorkshire is a Norman motte and bailey castle, built upon a Saxon royal palace, and used extensively during the English Civil Wars, when it suffered three prolonged sieges.  In that time, it went from being the property of a Norman Baron, to a powerful Dukedom, to the principal royal castle of the North of England.

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At the end of the Civil Wars the castle was pulled down by the people of Pontefract by order of Parliament.  The site was initially used as a market garden before it was leased by the Dunhill family for the cultivation of liquorice. Finally, it was converted into a park in 1880.  To this day the site remains a park and major tourist attraction in the town.

Now managed by Wakefield Council on behalf of the Duchy of Lancaster the castle has recently undergone a thorough restoration project seeing the ruins conserved and new visitor facilities created.

Parts of the site were excavated in the 1880s and again in the 1980s.  More recently, work commencing in 2017 to restore the site saw new areas excavated including the Gatehouse.

The Keep of Pontefract Castle courtesy of Wakefield Council.

As the Victorian excavations weren’t fully recorded or published, and more recent archaeology has been focused on areas where construction and conservation has taken place, this has left many parts of the site relatively unexplored.

The two areas we will be looking at as part of this project are the area from the Kitchens through to the Royal Apartments within the Bailey; and the northern ramparts below the royal apartments.

The first of those two is where a series of “service buildings” were sited according to historic maintenance records for the castle.  We know little more, but it was probably also the site of a gatehouse leading to a walkway to the Swillington Tower.  We hope this project will find some evidence of the footprint of the buildings, possible locations of fireplaces and to get an indication of how much survives below ground. 

Area occupied by the service buildings between the kitchens and Royal Apartments. courtesy of Wakefield Council

The second area to be investigated is an area outside of the curtain wall, which was subjected to heavy bombardment during the three sieges.  This may also be the location of a medieval garden, again mentioned in historical records, and Victorian walkways and paths. 

This area should include the bottom section of the walkway from the bailey down to the Swillington Tower. We hope to answer questions such as whether the earth mound at the side of the tower covers the remains of this walkway and how much of it survives under the start of the ramparts.

The site has seen little activity since the Victorian paths were laid, with that area falling into disuse relatively quickly.  This lack of later use raises the potential for evidence of all these things, but most excitingly the possibility of pinpointing further evidence of Civil War activity.

The outer ramparts looking from the Queens Tower back towards the Swillington Tower.

The project will see specialists from Wessex Archaeology conduct various forms of geophysics on the two areas including resistivity, magnetometry and ground penetrating radar.  The use of multiple techniques has been chosen to maximise the potential for making discoveries with the potential for quite complex buried remains being high.

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Plan of Pontefract Castle with hashed area the areas being surveyed, courtesy of Wakefield Council

Exploring Raby’s Medieval Past

The team at Raby Castle were delighted to hear that their application to the Castle Studies Trust for funding to support the creation of a digital model of the 14th century Nevill stronghold. The acual survey to create the model will not take place until May, but preparation is well underway including extensive documentary research by volunteeers. Their curator, Julie Biddlecombe-Brown who will oversee the project during 2022 reflects here on what the project will entail and what they hope to achieve.

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Raby Castle is one of the most impressive intact castles in the North of England. Built in the 14th century by the powerful Nevill family, it has a fascinating history. The castle was seized by the Crown in 1569 after the failed ‘Rising of the North’. In 1626 the castle was purchased by courtier Henry Vane the Elder and has remained in the family ever since. Over the last 300 years, successive generations have altered, updated and modernised parts of the building and although from the exterior, the 14th-century core is still evident, internal reworkings of the spaces mean that it is sometimes difficult to imagine and interpret the castle’s medieval past.

West Side of Raby Castle copyright Graeme Peacock, Raby Castle

In 2016, the castle was inherited by Harry Vane, Twelfth Baron Barnard. Under his stewardship, ambitious development plans were passed to enhance the visitor journey at Raby Castle, Park and Gardens. The dynamic scheme known as The Rising will restore and preserve historic buildings which have been without purpose for decades, providing contemporary event and exhibition spaces, retail and dining experiences and a visitor’s hub.  The transformation of the visitor offer at the castle, park and gardens include improved interpretation of the castle building. An important part of this for the Raby team is increasing our understanding of how the castle functioned during it medieval heyday. In 1378 Bishop Hatfield granted John Nevill a licence to crenellate reflecting a building that was changing from a fortified manor house to the castle we see today. Less than 50 years later, John’s son Ralph arranged the betrothal of his daughter Cecily to his young ward, Richard Duke of York; a marriage that would play a central role in the Wars of the Roses and ultimately in shaping British history. 

View from the inner-courtyard, showing The Keep and Clifford’s Tower ©Daniel Casson

With no significant collections in the castle to reflect this period, Raby’s greatest medieval asset is  the castle itself. Alterations over the past 400 years have reshaped the  building, modernising it for residents as tastes and technologies changed. Whilst it is still medieval in appearance, key features of the 14th century building have been lost. In order to explore how the castle may have looked before these alterations, our 2022 project will create a digital model of the castle that allows visitors then to view the castle’s past appearance based on our ongoing research. 

The creation of the digital model will be carried out by Durham University’s Archaeological Services, using a DJI S900 drone or equivalent. Photographs will be taken utilising a 14mm lens and 36 megapixel sensor, supported by RTK GNSS positioning. The data captured will then be uploaded and processed through Agisoft Metashape Professional and output as a 3D model utilising AutoCad Map 3D and giving the team the opportunity to ‘strip back’ known later additions and ‘rebuild’ known, lost features, such as the Barbican. The resulting model will be used in new interpretation at the castle, sharing our findings with our visitors.

View through the Nevill Gateway to the inner-courtyard and door to the Entrance Hall ©Raby Estates

Instrumental to the success of this project will be a team of Raby’s dedicated volunteers. A group of the castle’s regular volunteers formed a research group to work with the curator to pull together all known sources for the castle’s architectural changes to support this project. They have researched documentary sources including primary and secondary accounts, topographical pictures, maps and plans and in advance of the project will be surveying the castle walls. Their findings will be brought together in a portfolio of evidence which can then be reviewed by specialists from Durham University Archaeological Services who will be carrying out further research and eventually creating the model itself.

There has never been a full archaeological survey of Raby Castle and opportunities for research have been limited in the past. This project reflects the ambitions and vision of Lord and Lady Barnard, the castle’s owners who firmly believe that it is by understanding and sharing the castle’s past that we will secure its future. This project is part of that important story.

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Feature image: Raby Castle from a drone copyright Daniel Casson

Castle Studies Trust is going on its travels in 2022

In its latest round of grants the Castle Studies Trust has awarded £34,000 to five projects including two projects outside the UK. As well as covering a wide geographic area the projects will also undertake a broad range of technics to boost our understanding of castles.

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Dating medieval towers in the hinterland of Medieval Chalkida, Greece:

Stand-alone medieval towers, often part of castles or larger fortifications, are common in Central Greece. Often thought to have been built by the Frankish nobility during their period of dominance between 1204-1470, there is minimal evidence to back this up. By taking wood and mortar samples, the project aims to answer that question.

The present project forms part of the five-year survey ‘Beyond Chalkida: Landscape and Socio-Economic Transformations of its Hinterland from Byzantine to Ottoman times’ (authorised in July 2021 by the Greek State)

Samples will be taken from six towers of wood used laterally within tower walls to increase their structural strength, and mortar from within the core of the walls (both therefore probably

contemporaneous to the original period of construction). Specialists will use dendrochronological and

Carbon 14 methodology for the wood (8 samples), and optical microscopy, Scanning Electron Microscopy (SEM), and X-ray fluorescence (XRF) and diffraction (XRD) Spectroscopy (mortar – 21 samples).

Work will start at the earliest in late 2022 and may not actually take place until next year due to the time it is likely to take to get official permission from the government. 

Kilmacahill, Co. Westmeath

Geophysical survey of deserted medieval settlement close to Jamestown motte & bailey castle. The aim is to understand the morphology of settlement and its relationship with the castle and medieval monastery.

This survey will contribute to a larger project: the Human-Environmental Exchanges in the Landscapes of Medieval Ireland Project (HELM Project) which aims to use a combination of multispectral imaging, UAV drone survey along with geophysical survey to gain a much better understanding of the form of the deserted medieval village through non-invasive methods.

At time of writing it was unclear when the survey will take place.

Pontefract, West Yorkshire

Pontefract Castle: Service area between the kitchen and royal appartments copyright Angela Routledge, Wakefield Council

The project funded will be a geophysical survey of two parts of the castle, which during its history was the main royal castle in Northern England, not previously investigated. The survey will be of two areas of the castle using Magnetometry, Resistivity and Ground Penetrating Radar (GPR)

The focus is on parts of the castle not previously explored by  excavations in the 1980s, especially around the northern ramparts. This area stretches from the Swillington Tower towards the Kings Tower, and includes several earthwork features which remain unidentified, or unconfirmed.  Geophysical investigation is likely to reveal several interesting features including the link wall between the curtain wall and the Swillington Tower, which is unique in that it was built outside the main castle defences.

A second area that we have very little information on is part of the castle known as the “service buildings”. This area has never been excavated and we have very little knowledge regarding the layout or function of this part of the castle. 

As yet it is unclear when the survey will be undertaken.

Raby, Co Durham:

Aerial View of Raby Castle copyright Raby Castle

The Trust will be co-funding the project which aims to improve the understanding of the castle in the medieval period, especially around 1400 in the decades immediately after the licence to crenellate, with a buildings survey and development of a 3D model.

Once a stronghold of the Neville family, it moved into the ownership of the Vane family in 1626 and has been much altered and modernised, especially in the Victorian period, into a palatial family home.  Large sections of the medieval castle survive intact, albeit intersected and extended with more recent architectural additions.

This project seeks to strip back the more recent layers, to make sense of the medieval castle. Our aim is to create a 3D visualisation of Raby Castle in around AD 1400, helping us to visualise and to understand (where possible) how it functioned before the later additions.

In addition to boosting our understanding of the castle, the plan is also to train up a team of volunteers in how to carry out a building survey.

The aim is to start the survey work in April. 

Shrewsbury, Shropshire:

Shrewsbury Motte Top copyright Nigel Baker

This is the third project the Trust has funded on this important castle of the Welsh Marches and is an excavation of the motte top. The first two excavations in the inner bailey discovered that the original inner bailey was a lot smaller than it is today with little room for any substantial buildings, especially the royal hall.

This leaves only the motte and the aim is to understand the structural sequence and assess the character and the status of the buildings there: specifically to identify the royal hall known to be present during the Middle Ages.

The excavation is due to take place in the second half of July.

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Featured image Shrewsbury Castle by air courtesy of Shropshire Council

A large and eclectic crop of fascinating applications for the Castle Studies Trust to consider

The deadline for grant applications passed on 1 December. We’re going through the various projects now. Altogether the 12 projects, coming from the UK, Ireland and even one from Greece, are asking for £88,000. They cover not only a wide period of history but also a broad range of topics.

We will not be able to fund as many of these projects as we would like. To help us fund as many of these projects as possible please donate here: https://donate.kindlink.com/castle-studies-trust/2245.

In a little more detail here are the applications we’ve received:

Bedrule, Roxburghshire: The project aims to advance understanding of the role of the castle in the evolution of a well-defined rural community in SE Scotland between the 14th and 16th centuries using a variety of sources including archival research, LiDAR and GIS data analysis.

Berkeley, Gloucestershire: Using a variety of techniques including drone survey and archival research to understand the structure of the castle’s twelfth century shell keep, and then to develop a reconstruction drawing of what it could have looked like at that time.

Cavers Castle, Roxburghshire: Archaeological assessment of earthworks and early castle remains at Cavers Castle, Roxburghshire, which stands as a part-demolished ruin, using a variety of techniques such as geophysical survey, review of documentary and cartographic evidence and LiDAR.

Dating medieval towers in the hinterland of Medieval Chalkida, Greece: Stand-alone medieval towers, often part of castles or larger fortifications, are common in Central Greece. Often thought to have been built by the Frankish nobility during their period of dominance between 1204-1470, there is minimal evidence to back this up. By taking wood and mortar samples, the project aims to answer that question.

Dunoon, Argyll: The project will conduct a geophysical survey of Dunoon Castle mound and its immediate environs to determine the extent, nature and character of buried archaeological remains and will also provide signage to help illustrate what was found.

Galey, Co. Roscommon: Geophysical and topographical surveys to explore the possible motives behind the placement of, as well as  immediate landscape context, morphology and any attached settlement and industrial activity, that occurred at a lakeshore-sited late medieval Gaelic-constructed tower house castle.

Kilmacahill, Co. Westmeath: Geophysical survey of deserted medieval settlement close to Jamestown motte & bailey castle. The aim is to understand the morphology of settlement and its relationship with the castle and medieval monastery.

Millom, Cumbria: Geophysical survey of the area surrounding this 14th century castle to try to understand more about the landscape in which it was built.

Pontefract, West Yorkshire: Geophysical survey of the castle focusing on parts of the castle not previously explored by the excavations in the 1980s, especially around the northern ramparts.

Raby, Co Durham: The aim of the project is to improve the understanding of the castle in the medieval period, especially around 1400 in the decades immediately after the licence to crenellate, with a buildings survey and development of a 3D model.

Shrewsbury, Shropshire: To excavate the top of the motte of this important Marcher castle to understand the structural sequence and assess the character and the status of the buildings there. Specifically to identify the royal hall known to be present during the Middle Ages.

Sleaford Castle, Lincolnshire: Geophysical survey of the to context between the castle earthworks and the principal southern road of the town to establish if further remains of the castle exist in this direction (an area heavily during the 19th century) and establish if there were any links to the town other than the established route along Castle Causeway.

We will not be able to fund as many of these projects as we would like. To help us fund as many of these projects as possible please donate here: https://donate.kindlink.com/castle-studies-trust/2245

The applications have been sent to our assessors who will go over them. You can see how the assessment process works from our blog back in January 2016 https://castlestudiestrust.org/blog/2016/01/17/how-the-castle-studies-trust-selects-its-projects/