From a commercial kitchen to power generators and oil storage, the facilities were designed to keep residents holed up for as long as 30 days.

The 3.7-acre site is east of the town of Ballymena, the heartland of firebrand Protestant cleric turned peacemaker Ian Paisley until his death in 2014.

Fixtures and fittings are included in the price of the two-storey bunker, which opened in 1990.

(Editing by Brian McGee)