In January 1846 Sir George Colthurst of Ardrum, County Cork married the heiress Louisa Jane Jefferyes whose family had lived at Blarney since the beginning of the previous century. They had built a gothick extension onto the old MacCarthy castle on the site, but this residence was largely destroyed by fire in 1820 (although sections, such as the large central bow can still be seen). Over half a century later Lady Colthurst requested a new house be built on the estate, and a design for this was commissioned from the Belfast-born architect John Lanyon. The result, an extravagance of pinnacles, crow-stepped gables and conical-roofed turrets, merrily mixes Scottish baronial with fifteenth century French influences as if to reflect the Auld Alliance in which Ireland played no part.