© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Caerleon Legionary Fortress: Back Garden of No 4 Museum Street is a Roman legionary fortress located in Wales and protected by Cadw. The site lies upon Lower Devonian bedrock comprising mudstone, siltstone and sandstone, ancient sedimentary deposits laid down during the Early Devonian period. This stable geological foundation provided suitable ground for the substantial military infrastructure that once occupied the site.
The fortress represents one of the significant Roman military establishments in Britain, built to project imperial authority across the Welsh territories. Legionary fortresses of this type were permanent bases designed to house a full legion of approximately 5,000 soldiers, featuring organized defences, accommodation blocks, administrative buildings and specialist facilities for equipment maintenance and supply storage. The spatial arrangement of such fortresses followed standardized military planning principles that characterized Roman military architecture across the empire.
The protected status of this site ensures preservation of the archaeological resource for future study and understanding. Although substantial Roman remains and finds are recorded at Caerleon, the specific back garden location represents one of several known areas where fortress structures and deposits survive beneath the modern townscape, offering archaeologists opportunities to investigate the layout and daily operations of this important Roman military installation.
Caerleon Legionary Fortress: Back Garden of No 4 Museum Street is a scheduled monument protected by Cadw under reference MM239. View the official record →
Caerleon Legionary Fortress: Back Garden of No 4 Museum Street is a Roman legionary fortress located in Wales and protected by Cadw. It is designated a Scheduled Ancient Monument by Cadw under reference MM239.
Caerleon Legionary Fortress: Back Garden of No 4 Museum Street dates from the roman period, and is classified as a legionary fortress. It is one of over 32,000 scheduled monuments protected across the UK.
Caerleon Legionary Fortress: Back Garden of No 4 Museum Street is a Scheduled Ancient Monument, legally protected by Cadw — the body responsible for designating and safeguarding heritage sites in Wales. The official designation reference is MM239.
Several scheduled monuments lie within 10 km, including St Julian's Wood Camp (1.5 km), Newport Castle (3.6 km), St. Mary's Churchyard Cross, Llanwern (4.1 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Caerleon Legionary Fortress: Back Garden of No 4 Museum Street's history, each drawn from the record and mapped to the exact spot:
Every location is different. Not every section appears for every place, only what the historical record actually holds turns up in a report.
Caerleon Legionary Fortress: Back Garden of No 4 Museum Street stands on Lower Devonian Rocks (Undifferentiated), bedrock that formed in the Early Devonian. The rock here is mudstone, siltstone and sandstone.