Titanic’s Dock & Pump-House are rumored to be haunted by the ghosts of workers long passed.
Crumlin Road Gaol--Apparitions, faces, and shadows have been caught on camera. While only 17 people were hung here, many other prisoners are said to be here occupying every wing. The B-wing is where a famous photograph caught the face of a man in a coffin. A prison warden is also in this area and can be heard walking the halls. In the C-wing, a man walks, only to vanish into the air. And, in the D-wing, a man reportedly stands in the doorways and watches visitors. EVPs are quite common as are objects being thrown.
Belfast Flaxworks, an old linen mill, is haunted by Helena Blunden, a worker who fell to her death in 1912. Witnesses claim a femil voice might call their name or electrical equipment might malfunction or lights flicker. You can read more about her here https://seeksghosts.blogspot.com/2011/12/ghost-of-helena-blunden.html