Simon Delaney celebrates the stunning citadels of Eire. The Norman invasion of Ireland in the 12th century led to the mass-building of castles across the isle.

What have the Normans ever done for us? Simon Delaney salutes the Norman knights who led a castle building spree in Eire during the 13th and 14th centuries.

An educational journey around Ireland's fortresses. As Irish clans resisted Anglo-Norman settlers in the 1400s and 1500s, a new type of castle emerged: the tower house.

Simon Delaney takes viewers to the castles - from Limerick to Kilkenny - that played integral roles in the bloodiest period of Irish history: the 17th century.

With the advent of the cannon in the 18th and 19th centuries, castles such as Tullynally morphed from military strongholds into lordly family homes.

As political and social unrest swept Ireland in the 20th century, debt-ridden castles fell into disrepair and into the hands of the nouveau riche.