Nowadays, Kilkenny Castle is effectively three-sided. One of the four walls - and one of the great round drum towers - has disappeared over time.
Where did it go? Well, the Eastern wall and the North-Eastern tower were blown up during the 1650 Cromwellian siege of Ireland.
In 1922, the Butler family - namely Lord and Lady Ossory - were residents of the castle. The Irish Civil war, raged around them. Lord Ossory memorably wrote that he was woken at the "unreasonable hour of 5.30am" by his butler, who brought the news that Republican forces had seized and occupied his castle.
The gravestone of Daniel O’Connell in Glasnevin Cemetery, Dublin is made from Kilkenny black marble, and the stone was also used in the construction of Cobh Cathedral in Cork
Gulliver's Travels author, Jonathan Swift, attended Kilkenny College in the late 17th century, and a building at the college was named after him in 2007. Swift's fellow students included playwright William Congreve and the philosopher George Berkeley – after whom California’s Berkeley College is named.
Kilkenny, an inland county, is bordered by counties Wexford, Carlow, Laois, Waterford, and Tipperary. Geologically speaking it is mostly limestone, with areas of black marble around Kilkenny city. The rivers Nore, Suir, and Barrow flow through it.
In 1650 invading Cromwellian forces mounted an attack on Kilkenny castle and although it was initially successfully defended they eventually managed to take control of the city by another route.