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The Bivallate Rath with Souterrain is a substantial early Christian settlement near Lisburn, Northern Ireland, comprising a fortified residence and associated underground passage. The monument consists of a double-banked earthwork enclosure typical of raths from the early medieval period, with a souterrain—a stone-built subterranean chamber—integrated into the settlement. An adjoining rath annexe extends the defensive circuit, suggesting a dwelling of considerable status and complexity. Such multi-chambered underground structures served various purposes including storage, refuge and ritual functions within early Irish homesteads.
The site sits upon Palaeogene extrusive rocks, ancient mafic lavas and tuffs formed during volcanic activity millions of years before human settlement. This geological foundation provided the stone resources necessary for constructing the souterrain's corbelled or stone-lined passages, which characterise these monuments throughout early Christian Ireland. The local geology thus shaped both the monument's construction and its durability.
Now protected as a scheduled monument under Historic Environment Division reference 4521, this rath represents an important survival of early medieval settlement archaeology. Its double banks and elaborate souterrain system demonstrate the investment in defensive and practical infrastructure typical of elite ringforts from the 5th to 10th centuries, offering evidence of social hierarchy and agricultural wealth in early Christian Ulster.
Bivallate rath with souterrain & rath annexe is a scheduled monument protected by Department for Communities NI under reference 4521. View the official record →
The Bivallate Rath with Souterrain is a substantial early Christian settlement near Lisburn, Northern Ireland, comprising a fortified residence and associated underground passage. It is designated a Scheduled Ancient Monument by DfC Northern Ireland (NISMR) under reference 4521.
Bivallate rath with souterrain & rath annexe dates from the e.christ. period, and is classified as a rath & souterrain. It is one of over 32,000 scheduled monuments protected across the UK.
Bivallate rath with souterrain & rath annexe is a Scheduled Ancient Monument, legally protected by DfC Northern Ireland (NISMR) — the body responsible for designating and safeguarding heritage sites in Ni. The official designation reference is 4521.
Several scheduled monuments lie within 10 km, including Green mound. rath & multivallate motte (1.4 km), Tullyrusk fort. raised rath & plantation fort (2.1 km), Giant's grave. megalithic tomb (2.1 km).
This page is just one thread. A full Aubrey report pulls together 14 strands of Bivallate rath with souterrain & rath annexe'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.
Bivallate rath with souterrain & rath annexe stands on Unnamed Extrusive Rocks, Palaeogene, bedrock that formed in the Paleogene. The rock here is mafic lava and mafic tuff.