Everyone who visits Ireland wants to see a castle. But are you interested in ruins or do you want to stay in luxury in a castle that has reinvented itself as a hotel? With the increase in civil ceremonies for weddings, castle hotels are also doing a lively business in hosting the exchange of vows.

If you like your castles truly medieval then you are likely to be a connoisseur of ruins. On Northern Ireland's Antrim coast the ruins of Dunluce Castle looms broodingly over the Atlantic Ocean. The ruins have been reinvented recently as the set location for the House of Greyjoy on the hit television series "Game of Thrones." Northern Ireland also offers Carrickfergus and Enniskillen Castles for visitors who like castles old, but is better repair than a ruin. Carrickfergus Castle dates from the same era as Dunluce Castle; Enniskillen Castle is a mere youth having racked up only 600 birthdays.

Virtually every county in the Republic of Ireland will offer you an example of a ruined castle or one that has been restored and repurposed for the 21st century. One of my favourites is the ruined castle in Manorhamilton, Co. Leitrim that was used for barely a generation before it fell into disuse. So much effort was put into creating that fortress for such a short period of time before the lord was routed.

Ireland's important families - for example, the O'Carrols of Offally, the O'Rourkes of Breifne, the O'Flaherty's of Galway - would have had strongholds in the medieval period. With the historic invasions of the Normans up to the Flight of the Earls in the early 17th century, astles were mostly in the possession of Gaelic families or Anglo-Norman conquerors, like the de Courcy's of Carrickfergus. Trim Castle in Meath is another example of a medieval Anglo-Norman stronghold; the de Lacy family began to build their castle close to the River Boyne around 1176, making it contemporaneous with Carrckfergus.

With the defeat of King James at the Battle of the Boyne and the siege warfare techniques of Oliver Cromwell, the original military purpose of the castle had ceased. Some castles, like Dublin Castle became law courts and jails; it later became the hub government administration. Others, like Enniskillen Castle, became the home for garrisons. However, important families have always liked an architectural display of power and influence. A style often called 'Scottish Baronial' came into fashion all around the British isles in the 19th century.

These whimsical neo-Gothic castles were built by the Protestant Anglo-Irish aristocracy and gentry. Glenveagh Castle in Donegal is a complete example of the baronial style. But the castle was created at the cost of the tenants, who were cleared off as they did not figure in the aesthetic vision of Captain Adair and his American wife. This contrasts with the experience of the Gore-Booth family at Lisadell in Sligo, the next county over. There the landlord was so exercised by the plight of tenants during the Great Famine, that he paid for the passage of hundreds of emigrant tenants, indebting himself to the tune of £50,000 - a huge sum in that era.

Many of these 18th and 19th century castles and stately homes can now be visited. The National Trust in Northern Ireland opens many to the public for part of the year. In the Republic, some are in private ownership and open to the public, like Lisadell; many others have now become hotels. Ashford Castle is one of the most visited by overseas tourists, especially those with a love of golf. But almost every country in Ireland will offer you a few options. Even in a relatively aristocracy 'poor' country like Leitrim that had mostly absentee landlords there are two castle hotels - Lough Rynn and Kilronan Castles.

Whereever your Irish trip itinerary takes you, you are sure to be able to see both ruins of castles as well as having an opportunity to rest your head in a bed where the 'quality' used to sleep.