It is protected as a Grade B1 listed building and is one of the best-preserved examples of its type in the UK
A nuclear bunker built in South Belfast during the height of the Cold War is now home to one of Northern Ireland’s most important heritage collections.
The new archive facility for the Historic Environment Record of Northern Ireland (HERoNI) was opened this week at the former Belfast War Room in Mount Eden Park, Belfast.
The project secures the future of one of Northern Ireland’s most important heritage collections while giving new life to a significant Cold War landmark. Constructed in the early 1950s, the Northern Ireland Regional War Room was one of just 13 purpose-built Regional War Rooms established across the United Kingdom during the Cold War.
Designed to co-ordinate civil defence and regional government functions in the event of a nuclear attack, the building is recognised as one of the best-preserved examples of its type anywhere in the UK and is protected as a Grade B1 listed building.
The repurposed facility will provide a permanent, sustainable home for HERoNI, which documents more than 45,000 historic sites through maps, plans, records and photographs.
Opening the facility this week, communities minister Gordon Lyons said: “The opening of the HERoNI Archive Store represents an important new chapter in the history of the Belfast War Room, ensuring the continued preservation of both this remarkable historic building and the irreplaceable archive collections it now houses for the benefit of future generations.
“There is a unique relationship between the building’s original purpose and its new role. Once designed to safeguard government and society during a period of international uncertainty, the former Belfast War Room will now protect the records, knowledge and cultural memory that help future generations understand Northern Ireland’s rich and diverse heritage.
“This project demonstrates how our historic buildings can be adapted in innovative and sustainable ways, preserving not only the structures themselves but also the invaluable collections they can support.
“I would also like to acknowledge the contribution of the consultants, contractors and Department for Communities staff whose expertise and commitment made this innovative project possible.”
Documents included in the archive include records relating to more than 45,000 historic places, including archaeological sites, historic monuments and buildings, as well as industrial, marine and defence heritage sites. Its collections include drawings, maps, plans, documents and hundreds of thousands of photographs spanning all periods of Northern Ireland’s history.
The transformation of the War Room highlights the potential for the sustainable reuse of historic buildings. While the structure’s original design posed significant challenges for redevelopment, its distinctive features, including 1.5 metre-thick reinforced concrete walls, a windowless design and a network of small internal rooms, have proven highly suitable for archival storage.
These characteristics help maintain stable environmental conditions essential for the long-term preservation of sensitive historic records.
The building will be open for tours as part of European Heritage Days in September 2026.
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