Ruthin Castle is haunted by many ghosts. The ghost we know the most about is ‘Lady Grey’ or the Grey Lady. When she found out about the infidelity of her husband with one of the local peasant women, she killed her. Because of this Lady Grey was tried and convicted of murder and sentenced to death. She can be seen wandering the castle’s battlements and she has been seen in the Banquet Hall. Another haunt of the castle is the ghostly figure of a solider in armor wearing only one gauntlet (glove). There is a strange glowing ball of light that has been seen at the castle. Known as orbs it is believed that these orbs are the soul of the dead, the soul contains the intelligence, emotions and personality of human beings.

Ruthin Castle was built by Edward I in 1277; it was a strong baronial castle. The castle had two wards, the outer ward smaller than the inner ward. Five round towers originally guarded the inner ward. The remains of three can be seen today along with the ruins of the double towered gatehouse.

"The lordship of Dyffryn Clwyd was given to the Grey family in 1282 after Llywelyn’s defeat and the end of the principality of North Wales, and the history of the castle until 1400 seems to have been uneventful."

In the beginning of the 15th century Lord Grey, by devious means, had attempted to acquire the Dee estates owned by Welshman, Owain Glyndwr. For many years animosity has built up between them. When Glyndwr was ready to launch his bid for an independent Wales, Ruthin and Lord Grey were targeted for the first blow. The attack was a surprise to both England and Wales, but nowhere more so than the town of Ruthin. It was ravaged and burnt to the ground. The castle withheld the attack. Not to be done out of his vengeance, two years later Glyndwr defeated the English army at Vyrnwy and captured Lord Grey. He was imprisoned in Dolbadarn Castle, and was eventually released after a ransom of 10,000 marks was paid.

In 1644, during the Civil War, "Ruthin Castle resisted an attack by Parliamentary forces, who returned to besiege it two years later in 1646. The Royalist garrison surrendered to Major General Mytton and the castle was destroyed by order of Parliament. Part of the ruins were incorporated in a large castellated mansion which took the name of the castle, and was at one time the seat of Colonel Cornwallis West, a decedent of Sir Thomas Myddleton who was Lord Mayor of London in 1613, and who subsidized the publication of the first popular Welsh Bible."

Today the mansion is a luxury hotel, and all the old castle ruins are in the hotel grounds. Medieval banquets are held nightly, except Sundays, in the hotel, and the ruins may be inspected by permission of the hotel management.