Leixlip Castle was built in 1172 by Adam de Hereford, a follower of Strongbow, one year after the Norman Invasion of Ireland, and is one of the most continuously-inhabited buildings in Ireland. Leixlip means ‘salmon leap’ in Irish and this location on the confluence of the River Liffey and the River Rye has marked the frontier between the ancient kingdoms of Leinster and Brega. This was the site of the famous Battle of Confey in 917 whereby the Viking King of Dublin defeated the Irish King of Leinster. This was also the furthest in the Liffey where longships could be rowed and the point that marked the border of ‘The Pale’ during medieval times. Soon after the castle was built, it was used as a hunting base by King John when he was Lord of Ireland in 1185. In 1316 it withstood a 4-day siege by Edward Bruce’s army and in 1567 it was bought by Judge Nicholas White in whose family it remained until 1728. The next owner was William Conolly, of nearby Castletown House, who bought it along with 809 acres for £12,000. Famous tenants during his ownership include Archbishop Stone, the Protestant Primate (during the 1750s), the Viceroy Lord Townshend (1770s), Lord Waterpark, and Baron de Robeck (who drowned at the Salmon Leap!). In the 1920s it became the residence of the first French ambassador to the Irish Free State. In 1945 the castle was sold to William Kavanagh, prior to the purchase in April 1958 by The Hon. Desmond Guinness.