Castletown House.

This splendid Palladian mansion, arguably the grandest in Ireland, was begun in 1722 for William Connolly (1662-1729), the son of a Donegal innkeeper who, through astute dealings in forfeited estates after the Williamite wars, had become the richest man in Ireland. Connellyu was a Member of Parliament for Donegal and later Speaker of the Irish Parliament, the house was designed by Allesandro Galilei (1691-1737) also known for his work on the Lateran Basilica in Rome, the construction was overseen by Sir Edward Lovett Pearce.

Castletown was to become the inspiration for many other grand houses in Ireland, the interior was largely created during the time of Tom Conollys, the Speaker's great nephew, who inherited the property in 1758 when he was twenty-four. That same year he married the fifteen-year-old Lady Louisa Lennox, daughter of the second Duke of Richmond, whose older sister Emily had already married James, the Earl of Kildare, and was living nearby at Carton.

The new owners of the house soon began alterations and improvements to the house, largely led by Louisa who was altogether the stronger of the two, during the period of 1760 to 1766 the dining-room and work on the red and green drawing rooms. The green drawing-room, formerly the saloon, has been restored with green silk copied from the original fabric (1765) and gilded fillet copied from Chamber's design for the fillet in the gallery at Osterly Park. Tom Conolly died in 1803 but Lady Louisa lived on for many years. She eventually died in 1821, seated in a tent erected on the lawn in front of Castletown, for it was her wish that she should go looking at the house she had loved so much.

The house consists of a large three storied central block, connected to flanking wings by colonnades of of Ionic columns, one of the wings houses the kitchens, the other the stables. In 1758 it was inherited by Thomas Conolly, grandnephew of William. It was probably he who married Lady Louisa Lennox then 15, they employed the Fracini brothers to install the beautiful plaster work on the walls of the great stairwell.

From the back of the house an obelisk can be seen this impressive structure rising to 140 ft, consists of an obelisk set on top of a series of stone arches, it was designed by Richard Cassel at the behest of Conolly's widow as a means of creating work locally, after the severe winter of 1739 which led to famine.

The house was the headquarters of the Irish Georgian Society for a time. In 1994 Castletown was transferred into state care.