The city of Gloucester has a long and rich history. Founded in AD 97 by the Romans as Colonia Glevum Nervensis, under Emperor Nerv, it was granted its first charter in 1155 by Henry II. In 1216 Henry III, aged only ten years, was crowned with a gilded iron ring in the Chapter House of Gloucester Cathedral. Throughout the Middle Ages the city's importance is underlined by the fact that it contained a number of monastic establishments, including St Peter's Abbey, founded in 679, later Gloucester Cathedral; the nearby St Oswald's Priory, Gloucester, founded in the 880s or 890s; and Llanthony Secunda Priory, founded in 1136. The town is also the site of the 1643 Siege of Gloucester, during which the city held out against Royalist forces in the First English Civil War.  The Church of St Mary de Crypt lies at the heart of this fascinating city, and the indication is that it has existed as a religious house since the 11th century, almost certainly pre-dating the Conquest.  























1st edition 25" OS map 1844-1888



In 2017, Avon Archaeology Limited were commissioned by Discover DeCrypt to undertake a programme of archaeological monitoring and survey associated with the repair and modernisation of St Mary De Crypt Church and the adjacent Old School Room, to  comply with both Listed Building Consent and the Church of England Faculty for the development.  Additionally, a requirement for public engagement was attached to the grant of funding from Historic England. The two buildings are protected by statutory Listing; the church at Grade I and the attached school room at Grade II*.  During the renovation, the archaeological investigations encompassed three distinct elements: historic building recording, watching brief monitoring of all intrusive groundworks, and a community excavation.  

In the Old School Room, the floor level was reduced through hand excavation to allow for installation of underfloor heating. The excavation functioned as a small community project under the supervision of Avon Archaeology Limited staff. Volunteers were drawn from several local history and interest groups, including the Gloucester City Centre Community Partnership and the Gloucester and District Archaeological Research Group Buried medieval soil deposits were recorded and a collection of artefacts were recovered, which included Roman pottery, coins, tokens and an evocative toy cannon.   
No notable deposits or features were recorded, with the exception of a drain feature.  

St Mary De Crypt & the Old School Room,
Southgate Street, Gloucester

For Discover DeCrypt

Community Excavation & Watching Brief
St Mary De Crypt Church from Southgate Street


During the demolition of a modern wall that formed the north side of the Marylone passage, and below the wooden floor that formed a small utility space, an underground vault was unexpectedly encountered.

The Vault was acessed via a small hole and a step ladder, opening into a small rectangular room which sadly was empty, but for a few service cables. The official access, via a set of stone and brick steps had clearly been sealed long ago and subsequently forgotten, would have been located towards the north-east corner of the School Room building, on the north side of Marylone.   

Investigating the vault


Outside the church building, within the cemetery, a small linear trench was excavated adjacent to the east face of the Old School Room for the installation of a french drain.  Within the trench, a deposit containing a selection of 17th and 18th century pottery was found, as well as a spread of disarticulated human bone and the articulated remains of a small child, aligned east-west. The crowns of a further two adult sized skulls were also recorded, partially exposed in the west facing section of the trench at a depth of approximately 0.6m.  All articulated remains have remained in situ, while all disarticulated bone was replaced within the trench prior to backfilling.  

To the front of the church, in Southgate Street, a second trench was excavated to enable a waste connection from the church to the mains sewer system.  During its excavation, which was monitored under watching brief conditions, two large pieces of worked stone were recovered; one piece has been identified as part of a decorative structural cornice,  while the other is the upper part of an altar.  Both are of late 1st or early 2nd century date and are likely to have been associated with significant buildings of the Roman Colonia, Glevum.  The current hypothesis suggests that the stones were part of a Roman temple, possibly of Jupiter, which is likely to have stood on or close to the current location of St Mary De Crypt.    

Top: The Old School Room, the entrance to Marylone Passage via the arch left of the shot.  Bottom left: work in the central aisle of the church.  Bottom right: volunteers working in the school room.


Within the church, a photographic survey was carried out to record the 19th century pews and other features prior to removal.  A full survey was carried out of the ledger slabs which formed parts of the church floor to allow them to be accurately replaced, and a watching brief was undertaken during their removal as the tops of vaults were exposed.    
During works to replace stairs and install a lift at the north end of the school room, an unexpected discovery was made.  A small vault was found to extend below the alley known as Marylone.  Accessed by stone steps, the structure was built of stone and brick, with a vaulted brick roof, and was essentially empty, apart from a number of service cables. The vault was recorded as part of the building survey element of the project.   

The upper illustration is structural and would have formed part of the cornice of an important building.  The lower illustration is of the Roman Altar




Work continues on the Roman stonework, which will hopefully be displayed within a dedicated area of the church (to be confirmed).

A report on the stones produced by Dr Kevin Hayward, University of Reading and Dr Martin Henig will be published in Transactions of the Bristol and Gloucestershire Archaeological Society; fortcoming, 2021.


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