A scare at bedtime: Do the ghosts of star-crossed lovers Anne Knox and John McNaghten still roam Prehen
Thought to have been designed by local architect Michael Priestley, it was built in 1740 for Andrew Knox, MP for Donegal, after he married Prehen heiress Honoria Tomkins two years earlier.
Andrew Knox's family owned the house for 170 years. After being seized by the government after the 1914-18 war, Prehen House was brought back into another branch of the Knox family.
The Department of the Environment has listed Prehen as a grade A building of national importance, and it has bags of character.
Thriving with ghosts, Prehen House has strong links with the McNaghten story - he having lived there, and she, Miss Anne Knox, being the daughter of its original owner, Andrew Knox.
The scandal mainly involved Ann and McNaghten, who was a member of the same social class as Knox.
John fell in love with Ann and tried to be near her at all times. Andrew Knox opposed marriage between his daughter and McNaghten but the pair made strenuous efforts to stay in contact.
McNaghten claimed that he and Ann had secretly married. Desperate to protect his daughter, in 1760 Knox set out to transport Ann to Dublin in a coach, protected by armed outriders.
John McNaghten and several associates concealed themselves in a little road adjoining Burndennett Bridge, stopped the coach and a short argument ensued.
This was followed by gunfire and as a result McNaghten is said to have fired at the coach occupied by Andrew Knox and his daughter and Ann died from the bullet.
McNaghten fled but was eventually convicted and sentenced to be publicly hanged in an open field at Strabane for Ann's murder.
He spoke to the crowd, saying he loved his wife and had been kept from her. The rope broke and the crowd shouted for him to flee, but McNaghten declared that he was not going to be known as 'half-hanged McNaghten' and ordered the hangman to get on with his work.
The rope did not break again, and while McNaghten lost his life, his name lives on in the legend.
One of the fields adjacent to the house, which has a prominent tree, is known as 'Post Office Tree Field' - so called because it is believed that is was the tree under which McNaghten and Anne Knox secretly exchanged love letters.
Various visitors to Prehen House have over the years spotted the figure of a man loitering in the grounds, and a young woman in period costume is said to roam.