Blown up by a mad Physician 

Carlow Castle was built in 1213 by William Marshall on a strategic site close to the River Barrow. In 1361 it was strengthened when it became the headquarters of the Exchequer of Ireland when it was moved here from Dublin. The castle was attacked and withstood many attempted assaults in its history but its great ‘low point’ came not through war but by a physician named Middleton. Middleton attempted to convert the castle into a lunatic asylum in 1814 and when he decided to diminish the thickness of the walls by using explosives. He, however, made a gross miscalculation and ended up blowing most of the castle to pieces. All that remained were the 2 towers and a bit of the original wall. This is a great advertisement on how not to run an asylum

Thanks to Kenneth Williamson for great drone footage