SDO21780 - Lytchett Matravers, St Mary's Church. Geophysical Surveys in Search of a Tunnel, 2026

'St. Mary’s Church in Lytchett Matravers in Dorset dates from the late 12th century. The churchyard has two large yew trees, which may predate the church. The site is believed to have been of religious significance prior to the church being built there. There was a village built around the church in mediaeval times and a manor house was built near the church. The church and manor house were connected to each other by means of an underground tunnel. The mediaeval manor house was demolished and another building erected in the 19th century. The purpose of the tunnel is currently unknown, it may have been for smuggling purposes or was possibly a tunnel to facilitate a Roman Catholic priest to escape from the church after performing mass post-Reformation, or may have been for some other purpose. Several parishioners who have been involved in the church over many decades, recall seeing some younger members of the choir exploring down the tunnel in the 1950s. After this, the tunnel was then sealed off, and the exact location almost forgotten, but the existence of the tunnel is not in doubt. Interest in the tunnel’s location was rekindled by a growing appreciation of the church’s history. A key interest was to find the tunnel again, but using – if possible – non-invasive techniques. This was to respect historic burials and – if possible – to avoid having to get a faculty, particularly given the historic nature of the building. The owners of the subsequent manor house advised that builders had seen access to the tunnel in the old cellars of the mediaeval manor house, but these had been filled in and are no longer accessible. EDAS (East Dorset Antiquarian Society) supported the investigations with a GPR (Ground Penetrating Radar) survey. An area of 30 by 15 m was surveyed in the garden of the manor, which appears to show the tunnel location between the churchyard and the manor house. GPR results in the churchyard were unclear, due to the ground being so turned over with many burials in the churchyard over many centuries. To help investigations in the churchyard, BACAS (Bath and Counties Archaeological Society) offered to perform an ERT (Electrical Resistivity Tomography) survey. Survey lines were done to replicate some of the GPR lines for comparative purposes. The ERT surveys appear to show the tunnel’s location at either end, although there is some location discrepancy by the church. Some other clues have been provided by a 3D scan, observations on the wall separating the manor house lawn from the churchyard and a few other inferences. The project is ongoing and it is planned to excavate and regain access to the tunnel and – by studying its method of construction and if any historical remains (e.g. coins, pottery, etc.) are found – determine the likely age of construction and purpose (e.g. religious or economic), in the grounds of the current manor house.'