McDermott’s Castle: when to visit, what to see, and things to know

The infamous Instagram pictures of this island castle are recognised for its beauty across the Emerald Isle. Here is everything you need to know about McDermott’s Castle.

Lough Key in County Roscommon is home to over thirty wooded islands. The stunning McDermott’s Castle is on Castle Island, a small island the size of half an acre.

The island and castle are part of the larger Lough Key Forest Park, which, in recent years, has been open to the public.

A castle is believed to have stood on the island since the 12th-century, but it was reported to have been struck by lightning. When this happened, the castle went on fire and caused the magnificent residence to be destroyed, and numerous lives were lost.

Following this tragedy, the castle was rebuilt, and the castle that stands today dates back to the 18th-century. Although most of the castle is in ruins, some beautiful features are still intact.

A tragic legend – the history of McDermott’s Castle

The tragic legend of McDermott’s Castle.
Credit: Flickr / Greg Clarke

While there is so much history about this Roscommon castle and island, there is a tragic story surrounding them: the legend of Úna Bhán.

Úna was the daughter of the Chieftain, McDermott, whose name gives rise to the castle.

Úna fell in love with a boy who her father believed wasn’t good enough for her. As such, they had a relationship in secret.

The boy would swim across the lake to meet Úna, but unfortunately, on one occasion, he didn’t make it and subsequently drowned.

The story goes that Úna died of a broken heart and that two trees grew up over their graves, intertwining to form a lover’s knot.

When to visit – open all year round

The castle and island are open all year round.
Credit: Flickr / Elena

The Lough Key Park and Estate in County Roscommon is open all year round for the public to explore, and daily boat tours operate year-round throughout Lough Key.

The area is never too inundated with visitors, so our advice would be to head here when the weather is good, so you can experience Lough Key and McDermott’s Castle when it’s at its finest.

What to see – incredible castle ruins

What to see at McDermott’s Castle.

While much of the castle is in ruins, we suggest renting a boat from Lough Key Boats to explore the ruins for yourself.

Admire the sand-coloured stone walls, turrets, and empty windows that once overlooked the chilly Lough Key waters.

Much of the island is completely overgrown with ivy, but you can still get a sense of the grandeur present during the years the castle was lived in.

The neighbouring islands have ruins of churches, towers, and priories, and it is also believed that there are many unmarked or lost graves scattered across them.

Be sure to explore these as well – they really add to the beauty and magic of the area. Head to the nearby Trinity Island, which is where the tomb of Úna Bhán is said to be.

Things to know – insider info

Things to know about McDermott’s Castle.

Castle Island was up for sale in 2018 for just €90,000 but was taken off the market.

While the castle is described as being in a “perilous state”, we can only imagine how beautiful McDermott’s Castle would be if it got restored to its former glory!

The Nobel Prize for Literature winner W.B. Yeats visited Castle Island in 1890 and considered setting up an art centre there. He loved the island so much that he attempted to buy the castle, but his attempts were unsuccessful.

The island and castle featured in an episode of the Emmy award-winning television sitcom series, Moone Boy. In the episode, the island was the residence of the mysterious Island Joe, played by Pat Shortt.

Parking is available in Lough Key Forest Park at the cost of €4 per day. However, if you spend €20 or more, you get free parking.

You will be glad to know that the cost of parking goes towards the upkeep of the beautiful park!

What’s nearby – what else to see

Check out Moylurg Castle while you're in the area.

The Lough Key Forest Park is definitely worth exploring while in the area as it is one of the most beautiful parks in Ireland.

It is home to 800 hectares of picturesque park and woodland. They have an adventure park with everything from ziplining to a treetop canopy walk, so there is something for big and small kids alike to enjoy.

Take a trip underground as you navigate the old servant tunnels that are under Rockingham House.

There is a self-guided audio tour so that you can learn about the house’s history as you go. Or head to the top of Moylurg Tower for stunning views across Lough Key and of McDermott’s Castle.

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