Following our earlier article about the local listing of the Coventry spigot mortar off Bennetts Road, we are pleased to report that a second World War II defensive structure — located beside the Oxford Canal off Shilton Lane — is now the subject of a Local List consultation.
This is an important step forward in recognising Coventry’s surviving wartime defence network.
A Growing Picture of Coventry’s Stop Line
The structure in question is a 29mm Blacker Bombard spigot mortar — a rare surviving example of an emergency anti-tank weapon installed during the dark days of 1940–42, when invasion was considered a real threat.
Designed by Lieutenant Colonel V.V.S. Blacker, these weapons were mounted on circular concrete pedestals known as “thimbles”, with a central steel pintle onto which the mortar could be fixed. They were typically positioned at strategic defensive points as part of wider “stop-line” systems intended to slow or repel enemy advances.
The Bennetts Road example, which was locally listed earlier this year, was the first to be formally recognised within the city. However, publicity surrounding that designation prompted further discoveries.
We now know that three spigot mortars survive within Coventry’s boundary:
- Bennetts Road, Keresley (already locally listed)
- Shilton Lane, alongside the Oxford Canal (the subject of this listing process)
- Staircase Lane, Allesley
There is also a fourth example just outside the city boundary on the other side of the canal to the Shilton Lane one.
What initially appeared to be an isolated survival is now clearly part of a broader defensive line protecting the northern approaches to Coventry.
The Shilton Lane Site
The Shilton Lane mortar sits beside the Oxford Canal towpath, just beyond Stone Bridge. It occupies a small opening in the tree line, bounded by the canal to the north and the M6 corridor to the south — a location that underlines its defensive logic.
A site visit in May 2025 confirmed that the structure survives in good condition. The circular concrete pedestal remains largely intact, although part of the outer casing has been lost. The central steel pintle is still in place.
Significantly, this example retains a surviving ammunition locker — something not present at the Bennetts Lane site. Brickwork and rubble visible in the surrounding area suggest there may be additional associated features below ground.
Specialist advice indicates that the steel pintle lacks the circular platform normally seen beneath it, though this may represent a local construction variation rather than damage.
Evidence from the Air
One of the most exciting elements of the officer’s report is the inclusion of a 1946 RAF aerial photograph. The image shows the canal corridor far more clearly than today, before vegetation growth obscured the landscape.
Remarkably, four spigot mortar positions are visible along this stretch of canal in the photograph — including the Shilton Lane example, one on the opposite bank, the Warwickshire example beyond the city boundary, and a further position to the east.
The photograph suggests associated trenching and structural features around the emplacements. This strengthens the argument that the canal formed part of a coordinated defensive line.
The report concludes that there is strong potential for further archaeological evidence in the surrounding landscape.
Why Local Listing Matters
Historic England previously assessed the Bennetts Lane mortar for national listing but concluded that, while significant, it did not meet the threshold for national designation. Local listing was recommended instead — recognising its wartime value within a Coventry context.
The Shilton Lane report assesses the site against Coventry’s Local List criteria and finds:
- Historic value: Medium to high — as part of Coventry’s WWII defence network.
- Rarity: Medium to high — few such emplacements survive nationally, and even fewer locally.
- Integrity: Medium to high — with the added importance of a surviving ammunition locker.
- Group value: Increasingly significant as further examples have been identified.
- Coventry identity: Strong — these structures represent a direct material response to the threat faced by the city during the Second World War.
- Evidential value: Medium to high — with clear archaeological potential.
In short, this is not an isolated concrete relic. It is part of a defensive landscape that is only now being properly understood.
Public Interest Driving Discovery
The officer’s report highlights something particularly encouraging: public engagement has played a major role in identifying these sites.
The Bennetts Road mortar was first recorded during archaeological work in 2022. Publicity about its local listing prompted residents and researchers to come forward with information about further examples.
Interest in Coventry’s wartime heritage is clearly growing — and rightly so. The spigot mortars are modest structures, but they speak directly to the reality of 1940s Coventry: a city under sustained threat, responding rapidly and pragmatically.
What Happens Next?
The Council’s Archaeology and Conservation Team are inviting comments on the nomination for local listing.
As with the Bennetts Road example, it is anticipated that there will be strong public support for recognising this structure.
Local listing does not prevent change in the way national designation does, but it does ensure that the asset’s heritage value is recognised and taken into account in planning decisions. It is an important step in protecting Coventry’s historic environment.
A Defensive Line Re-emerging
Taken together, the identified spigot mortars along the northern edge of Coventry suggest that significant elements of the city’s WWII stop-line survive — albeit hidden in tree lines, canal banks and hedgerows.
There is now real scope for further research:
- Mapping the defensive perimeter
- Understanding firing ranges and intervisibility
- Exploring regional construction techniques
- Investigating surviving trench systems and associated features
What began as a single discovery is evolving into a wider story about Coventry’s wartime landscape.
Coventry Society welcomes this progress and has submitted its own support for the local listing. We also encourage society members and the wider public to engage with the consultation process. You can read the supporting documents and respond to the consultation here. The deadline is 9th March 2026. You may need to register if this is the first time you have responded to a planning consultation.
Coventry’s history is not just found in its medieval core or post-war reconstruction — it also lies in these quiet, overlooked remnants of a moment when the city prepared for the possibility of invasion.
We will continue to follow developments and provide updates as the consultation progresses.