Hazelwood was designed for Owen Wynne by the architect Richard Castle and built between 1720 and 1740. Reverend William Henry's account of Sligo in 1739 contains a detailed account of the house. Wilson describes it in 1786 as "a fine and elegant seat". It remained the home of the Wynne family for 200 years. At the time of Griffith's Valuation it was owned by John Wynne and was valued at £120. The estate was sold to the Land Commission in the 1920s and the house has had various uses including army accommodation, psychiatric hospital and more latterly, part of an industrial building. Though neglected it survives intact.