Throughout its history, Northern Ireland has had a rich heritage of mining across the country. This has resulted in over 2,400 known abandoned mine works. Access to these mines is dangerous and strictly prohibited.
Abandoned mines and their location
Abandoned mines are old mines where the owner no longer owns the property or the owner no longer exists. The mines contain vertical shafts and horizontal adits extending underground to great distances. The deepest shaft in Northern Ireland is a 366 metre vertical drop.
The Department for the Economy now owns and monitors all abandoned mines. You can view where the abandoned mine works are on the Geological Survey of Northern Ireland (GSNI) GeoIndex. To display them on the GeoIndex:
- click on 'Map layers' at the top of the screen
- click on 'Historic Mine Workings (Group)'
- check the boxes marked 'Shafts and Adits' and 'Mine Abandonment Plans'
The dangers of abandoned mines
Old mine workings are extremely hazardous and should never be entered. Most of the old mines have fallen into a state of disrepair and have a number of dangers including:
- hidden shafts
- internal collapse
- toxic and combustible gases
- lack of oxygen
All abandoned mines in Northern Ireland have been sealed and have warning notices.
Other dangers with abandoned mines
The greatest risk with old mines is collapse or subsidence of the overlying surface. This can take the form of sudden or long-term movement. Other risks include the emissions of contaminated water or gas.
What to look out for and how to report it
Causes for concern in areas containing abandoned mines are:
- rumblings and ground tremors
- a sudden hole appearing
- subsidence or unusual cracking of the surface
- recent structural damage to buildings and infrastructure
- water emissions from mines
- if you see a someone entering a mine
- damage to mine gates and fences
If any of these events occur you should keep a safe distance from the mine and tell GSNI immediately or the emergency services: