It was the 11th Lord Blayney who had the modern Blayney Castle (also known as Castle Blayney) constructed around the year 1800. In 1799 Lord Blayney commissioned Robert Woodgate, a former student of Sir John Soane, to design the new Blayney Castle. Woodgate, a distinguished young architect, had first come over to Ireland in 1791 to supervise Soane's plans for Baronscourt, the new country house of John Hamilton, 1st Marquess of Abercorn, near Newtownstewart in County Tyrone. The new Blayney Castle was built in a restrained late Georgian style. It is thought that this new 'castle' (in reality a country house), located in the townland of Onomy, was built close to the site of the original Blayney Castle, of which nothing now survives above ground. The house built for the 11th Lord Blayney was later, in the 1850s and early 1860s, substantially altered and enlarged for Henry Thomas Hope and his wife.