Ireland is home to some of the best castles in Ireland, with more than 30,000 historic sites scattered across its landscapes. From imposing medieval fortresses to romantic lakeside ruins, these iconic landmarks tell the story of Ireland’s rich heritage and centuries of history.
While many visitors discover Ireland’s castles by road, exploring them by boat offers a completely different experience. Cruising along the River Shannon, Lough Erne or the Shannon-Erne Waterway allows you to admire ancient fortresses from the water, moor in charming riverside towns and uncover hidden gems at your own pace.
If you’re planning a boating holiday in Ireland, combining scenic cruising with castle visits is one of the most rewarding ways to explore the island. Whether you’re travelling for history, photography or simply to enjoy Ireland’s spectacular scenery, these historic landmarks are sure to be the highlight of your journey.
Number of castles | Best boating region | Best season | Boat licence required | Ideal cruise length |
|---|---|---|---|---|
10 | River Shannon & Lough Erne | May-September | No | 7 days |
Here are the 10 best castles in Ireland that are easy to visit during a boating holiday.
1. McDermott's Castle (County Roscommon)
Perched on Castle Island in the middle of Lough Key, McDermott’s Castle is one of Ireland’s most enchanting landmarks. Dating back to the 12th century, the castle was once the stronghold of the powerful McDermott clan and has inspired countless local legends over the centuries. Surrounded by calm waters and ancient woodland, its fairytale setting has made it one of the most photographed castles in Ireland.
Although the island is not generally open to visitors, the castle is best appreciated from the water. Cruising across Lough Key offers uninterrupted views of the dramatic ruins rising above the trees, creating one of the most memorable moments of any Shannon boating holiday.
Why visit McDermott's Castle by boat?
There’s no better way to admire McDermott’s Castle than from your cruiser. The peaceful waters of Lough Key provide exceptional photo opportunities, while the surrounding forest park offers walking trails, cycling routes and family-friendly attractions nearby. It’s a magical stop that perfectly combines history, nature and some of Ireland’s most beautiful scenery.
Highlights
- Iconic castle on its own islan
- Spectacular views across Lough Ke
- One of Ireland’s most photographed castle
- Beautiful surrounding forest park and walking trails
Best departure base to visit McDermott's Castle
Carrick-on-Shannon is the ideal departure base for visiting McDermott’s Castle. A scenic cruise north to Lough Key makes this one of the most popular routes for visitors looking to experience one of the best castles in Ireland from the water.
2. Portumna Castle (County Galway)
Located on the northern shores of Lough Derg, Portumna Castle is one of the finest examples of Renaissance architecture in Ireland. Built in 1618 for Richard Burke, the 4th Earl of Clanricarde, the castle combines the elegance of a stately home with the defensive features of a medieval fortress. Although a fire damaged part of the building in the 19th century, extensive restoration work has brought many of its grand rooms back to life.
Today, visitors can explore beautifully furnished interiors, formal walled gardens and peaceful woodland trails managed by the Office of Public Works. The castle’s location beside the River Shannon also makes it an ideal stop during a boating holiday.
Why visit Portumna Castle by boat?
Approaching Portumna by water is one of the highlights of a Shannon cruise. After mooring nearby, you can easily spend a few hours visiting the castle before enjoying lunch in the lively harbour town. The surrounding area also offers scenic walking and cycling routes, making it a perfect stop for a full day ashore.
Highlights
- One of Ireland’s best-preserved Renaissance castles
- Beautiful formal gardens and riverside walks
- Easy access from the River Shannon
- Excellent marina within walking distance
Best departure base to visit Portumna Castle
Banagher is the ideal starting point for reaching Portumna Castle while exploring Lough Derg and the Lower Shannon.
3. Clonmacnoise Monastic Site (County Offaly)
Although not a castle in the traditional sense, Clonmacnoise is one of Ireland’s most remarkable historic landmarks and deserves a place on any itinerary exploring the country’s heritage. Founded in the 6th century by St. Ciarán, this ancient monastic city became a major centre of religion, learning and craftsmanship, attracting scholars and pilgrims from across Europe for hundreds of years.
Located on the banks of the River Shannon, Clonmacnoise is home to impressive stone churches, beautifully carved high crosses, round towers and centuries-old grave slabs. Its peaceful riverside setting creates a unique atmosphere, making it one of the most memorable stops along the Shannon Navigation.
Why visit Clonmacnoise by boat?
Arriving at Clonmacnoise by boat offers a truly special experience. As you cruise along the River Shannon, the ancient round towers gradually appear above the surrounding landscape, providing one of the most iconic views on Ireland’s inland waterways. After mooring nearby, you can easily spend several hours exploring the site and its visitor centre before continuing your journey.
Highlights
- One of Ireland’s oldest monastic settlements
- Magnificent high crosses and round towers
- Stunning riverside location
- Easy access from the River Shannon
Best departure base to visit Clonmacnoise
Both Carrick-on-Shannon and Banagher provide excellent starting points for visiting Clonmacnoise, making it an ideal stop on cruises through the central River Shannon.
4. Crom Castle (County Fermanagh)
Nestled on the shores of Upper Lough Erne, Crom Castle is one of Northern Ireland’s most picturesque historic estates. Surrounded by ancient woodlands, peaceful lakes and the beautiful Crom Estate Nature Reserve, the Victorian castle stands on land that has been home to the Crichton family for centuries. Although the castle itself is privately owned and not generally open to the public, its spectacular setting and extensive estate make it a must-see destination for anyone cruising Lough Erne.
Visitors can explore scenic walking trails, discover the ruins of the original 17th-century Crom Castle, and enjoy one of the finest natural landscapes in County Fermanagh. The combination of history, wildlife and tranquil waterways makes this one of the highlights of a Lough Erne boating holiday.
Why visit Crom Castle by boat?
Approaching Crom Estate by boat offers a unique perspective on one of Ireland’s most beautiful lakeside estates. Mooring facilities nearby allow visitors to explore the estate on foot, where peaceful woodland walks, historic ruins and breathtaking lake views await. It’s an ideal stop to relax, enjoy nature and experience a quieter side of Ireland’s rich heritage.
Highlights
- Beautiful Victorian castle and historic estate
- Ruins of the original Crom Castle
- Scenic woodland and lakeside walking trails
- Excellent wildlife spotting on Upper Lough Erne
Best departure base to visit Crom Castle
Bellanaleck is the perfect departure base for exploring Crom Estate and the wider Lough Erne waterway, including nearby Enniskillen Castle, Castle Archdale and Devenish Island.
5. Enniskillen Castle (County Fermanagh)
Perfectly positioned between Upper and Lower Lough Erne, Enniskillen Castle has stood guard over one of Ireland’s most strategic waterways for almost 600 years. Built in the early 15th century by the Maguire chieftains, the castle later became an important military stronghold before being transformed into one of Northern Ireland’s leading heritage attractions.
Today, visitors can explore two fascinating museums within the castle grounds. The Fermanagh County Museum tells the story of the region’s rich history, while The Inniskillings Museum highlights the heritage of the famous local regiments. Surrounded by the waters of the Erne and the lively town centre, Enniskillen Castle is an essential stop on any Lough Erne cruising itinerary.
Why visit Enniskillen Castle by boat?
Arriving by boat couldn’t be easier, with convenient moorings just a short walk from the castle. After exploring the exhibitions, visitors can stroll through Enniskillen’s charming streets, browse independent shops or enjoy a meal in one of the town’s welcoming cafés and traditional pubs.
Highlights
- Impressive 15th-century fortress
- Two award-winning museums
- Easy access from the marina
- Perfect base for exploring Enniskillen
Best departure base to visit Enniskillen Castle
Bellanaleck is the ideal departure base, with Enniskillen Castle only a short cruise away. It’s the perfect first stop when exploring the beautiful waterways of Lough Erne.
6. Castle Archdale (County Fermanagh)
Set within the peaceful surroundings of Castle Archdale Country Park, the ruins of Castle Archdale offer a fascinating glimpse into County Fermanagh’s rich history. Originally built in the early 17th century by the Archdale family, the castle was destroyed during the Irish Rebellion of 1641 and never fully rebuilt. Today, its atmospheric remains are surrounded by mature woodland, lakeside trails and one of Northern Ireland’s most scenic country parks.
The estate also played an important role during the Second World War, serving as a flying boat base for the Royal Air Force. Visitors can learn more about this remarkable chapter of history through informative displays and walking routes that explore both the castle ruins and the surrounding landscape.
Why visit Castle Archdale by boat?
Castle Archdale is a peaceful stop for boaters cruising Lower Lough Erne. Mooring nearby allows easy access to the country park, where you can enjoy gentle woodland walks, spot local wildlife and explore the historic ruins at your own pace. It’s an excellent destination for anyone looking to combine history with nature during their cruise.
Highlights
- Historic 17th-century castle ruins
- Beautiful lakeside woodland walks
- Second World War heritage
- Excellent wildlife and birdwatching opportunities
Best departure base to visit Castle Archdale
Bellanaleck is the best starting point for visiting Castle Archdale. It’s an easy and scenic cruise through Lower Lough Erne, making it a popular stop alongside Enniskillen Castle and Crom Estate.
7. Carrick-on-Shannon Castle (County Leitrim)
Although little remains of Carrick-on-Shannon Castle today, its history is closely linked to one of Ireland’s most popular boating destinations. Originally built during the 16th century to control an important crossing on the River Shannon, the castle played a strategic role in the region before being destroyed during the Cromwellian campaigns in the mid-17th century.
While the original fortress has largely disappeared, Carrick-on-Shannon has evolved into the vibrant boating capital of the River Shannon. Visitors can still discover the town’s rich heritage through its riverside setting, historic streets and welcoming atmosphere. With its lively pubs, local restaurants and independent shops, it’s an ideal place to begin or end a cruising holiday.
Why visit Carrick-on-Shannon by boat?
Arriving by boat is the perfect way to experience the town. As one of the busiest marinas on the Shannon, Carrick-on-Shannon offers excellent facilities and easy access to local attractions. It’s also the ideal starting point for exploring nearby highlights such as Lough Key, McDermott’s Castle, Clonmacnoise and Athlone Castle. Whether you’re spending your first or last night aboard, the town offers plenty of opportunities to relax, dine and experience traditional Irish hospitality.
Highlights
- Historic town on the River Shannon
- Ireland’s leading boating destination
- Excellent restaurants, pubs and marina facilities
- Perfect gateway to Lough Key and central Shannon attractions
Best departure base to visit Carrick-on-Shannon Castle
Carrick-on-Shannon is one of Carrickcraft’s main marina bases and the perfect starting point for exploring the central River Shannon. From here, you can easily cruise towards Athlone, Clonmacnoise, Lough Key and many of the best castles in Ireland featured in this guide.
8. Rindoon Castle (County Roscommon)
Hidden on the eastern shores of Lough Ree, Rindoon Castle is one of Ireland’s most fascinating medieval ruins. Built in the early 13th century, the fortified settlement once formed part of a thriving Norman town complete with defensive walls, a church, a harbour and merchant buildings. Today, the peaceful ruins offer a glimpse into Ireland’s medieval past, surrounded by rolling countryside and the tranquil waters of one of the River Shannon’s largest lakes.
Unlike many of Ireland’s more famous castles, Rindoon remains largely untouched by mass tourism. Its secluded location and unspoilt setting make it a rewarding destination for visitors looking to discover a lesser-known historic site during their boating holiday.
Why visit Rindoon Castle by boat?
Mooring at Lecarrow provides the perfect gateway to explore the beautiful surrounding woodland trails and enjoy a scenic one-hour walk to the historic ruins of Rindoon Castle. Along the way, you’ll discover peaceful lakeside landscapes before reaching the medieval site, where ancient stone walls and the remains of the old settlement overlook the shores of Lough Ree. While Rindoon Jetty itself serves as a safe harbour and offers views of the castle from the water only, Lecarrow is the ideal starting point for visitors wishing to experience both the area’s natural beauty and rich heritage.
Highlights
- One of Ireland’s best-preserved medieval fortified settlements
- Spectacular location on the shores of Lough Ree
- Quiet walking trails and panoramic lake views
- A hidden gem away from the main tourist routes
Best departure base to visit Rindoon Castle
Carrick-on-Shannon is the ideal departure base for cruising south towards Lough Ree. Rindoon Castle can easily be included alongside visits to Athlone, Clonmacnoise and McDermott’s Castle on a week-long Shannon itinerary.
9. King John's Castle (County Limerick)
Overlooking the River Shannon in the heart of Limerick, King John’s Castle is one of Ireland’s most impressive medieval fortresses. Built in the early 13th century on the orders of King John of England, the castle has witnessed centuries of conflict, trade and political change. Its commanding position on King’s Island made it a vital defensive stronghold, protecting one of the country’s most important river crossings.
Today, the castle is one of Ireland’s leading heritage attractions. Interactive exhibitions, archaeological discoveries and reconstructed medieval scenes bring its fascinating history to life, while the impressive towers and battlements offer spectacular views across the River Shannon and the city beyond.
Why visit King John's Castle by boat?
Mooring at Lecarrow provides the perfect gateway to explore the beautiful surrounding woodland trails and enjoy a scenic one-hour walk to the historic ruins of Rindoon Castle. Along the way, you’ll discover peaceful lakeside landscapes before reaching the medieval site, where ancient stone walls and the remains of the old settlement overlook the shores of Lough Ree. While Rindoon Jetty itself serves as a safe harbour and offers views of the castle from the water only, Lecarrow is the ideal starting point for visitors wishing to experience both the area’s natural beauty and rich heritage.
Highlights
- One of Ireland’s best-preserved medieval fortified settlements
- Spectacular location on the shores of Lough Ree
- Quiet walking trails and panoramic lake views
- A hidden gem away from the main tourist routes
Best departure base to visit King John's Castle
Banagher is an ideal departure base for exploring the southern River Shannon. Cruising south takes you through some of the region’s most scenic waterways to Killaloe, the southernmost point of the navigation, where you’ll find historic streets, riverside cafés and beautiful lakeside scenery. From Killaloe, the city of Limerick can be reached in around 30 minutes by taxi, making it an easy option for those wishing to explore the city as part of their wider Shannon itinerary.
10. Athlone Castle (County Westmeath)
Overlooking one of the most important crossings on the River Shannon, Athlone Castle has played a key role in Irish history for more than 800 years. Originally built by the Normans in the 13th century, the fortress has witnessed Viking raids, medieval battles and the famous Siege of Athlone in 1691.
Today, the castle has been transformed into a modern visitor experience featuring interactive exhibitions, audiovisual displays and panoramic views from the battlements. Its central location also makes it one of the easiest castles to visit during a Shannon cruising holiday.
Why visit Athlone Castle by boat?
Athlone is one of the most popular stops for boaters travelling along the River Shannon. You can moor in the town centre and reach the castle within a few minutes on foot. After your visit, enjoy the vibrant atmosphere of Athlone with its excellent restaurants, traditional pubs and riverside cafés.
Highlights
- Interactive visitor centre
- Historic Norman fortress
- Easy marina access
- Perfect stop for shopping, dining and sightseeing
Best departure base to visit Athlone Castle
Banagher is the best departure base, with Athlone typically reached after a comfortable day’s cruising north along the River Shannon.
Why Explore Ireland's Castles by Boat?
Exploring Ireland’s castles by boat offers a completely different perspective on the country’s history and landscapes. Many of these impressive fortresses were originally built beside rivers and lakes to control important waterways, defend territories, or protect trade routes. Arriving by cruiser allows you to experience these historic sites much as medieval travellers once did.
Unlike a traditional road trip, a boating holiday lets you travel at a slower pace, stopping in charming riverside towns, peaceful marinas, and hidden natural spots that many visitors never discover. Whether you’re cruising the River Shannon, navigating Lough Erne or exploring the Shannon-Erne Waterway, every day brings new scenery and fascinating heritage.
Benefits of visiting castles by boat
- Discover Ireland from a unique waterside perspective.
- Moor close to many historic towns and visitor attractions.
- Enjoy flexible itineraries without changing hotels every night.
- Experience peaceful cruising through Ireland’s beautiful inland waterways.
- Combine history, nature, local pubs and traditional Irish villages in one holiday.
Plan Your Castle Adventure with Carrickcraft
Carrick-on-Shannon
Carrick-on-Shannon is an excellent starting point for exploring the central River Shannon. From here you can comfortably cruise to:
- Athlone Castle
- Clonmacnoise
- McDermott’s Castle
- Lough Key
This route combines medieval history with lively waterfront towns and some of Ireland’s most beautiful lake scenery.
Banagher
Located on the Lower Shannon, Banagher is the ideal departure point for exploring Lough Derg and southern sections of the river. Highlights include:
- Portumna Castle
- Clonmacnoise
- The heritage town of
- Killaloe
- Scenic cruising across
- Lough Derg
This route is perfect for travellers who enjoy combining heritage sites with nature and waterside villages.
Bellanaleck
Situated close to Upper Lough Erne, Bellanaleck is the gateway to Northern Ireland’s spectacular lakelands. Popular castle visits include:
- Enniskillen Castle
- Castle Archdale
- Crom Estate
- Devenish Island
This area offers quieter cruising, abundant wildlife and some of the most peaceful waterways in Ireland.
Best Time to Visit Ireland's Castles by Boat
Season | Why Visit? | What to Expect? |
|---|---|---|
Spring (April-May) | Perfect for peaceful cruising and nature lovers. | Blooming wildflowers, quieter waterways, mild temperatures and beautiful gardens, especially around Portumna Castle and Lough Derg. |
Summer (June-August) | The best time for long cruising days and sightseeing. | Warm weather, extended daylight hours, lively towns, guided castle tours, local festivals and bustling marinas. |
Autumn (September-October) | Ideal for relaxed cruises and stunning scenery. | Fewer boats on the waterways, colourful autumn landscapes, pleasant temperatures and excellent photography opportunities around the River Shannon and Lough Erne. |
Why a Boating Holiday Is the Best Way to Discover Ireland's Castles ?
A boating holiday is one of the most rewarding ways to discover the best castles in Ireland. Cruising along the River Shannon, the Shannon-Erne Waterway or Lough Erne lets you explore historic castles, picturesque villages and stunning landscapes at a relaxed pace.
Many of Ireland’s castles were built beside rivers and lakes, making them even more impressive when approached from the water. With no boating licence required, a self-drive cruiser is an easy and enjoyable way to combine history, nature and adventure.
Whether you depart from Carrick-on-Shannon, Banagher or Bellanaleck, you’ll have easy access to some of Ireland’s most iconic castles and hidden gems.
Frequently Asked Questions
Can you visit Ireland's castles without a boating licence?
Yes. Self-drive cruisers can be hired without a licence, and full boat handling instruction is provided before departure.
Which castles are easiest to reach from the River Shannon?
Athlone Castle, Portumna Castle, Clonmacnoise and King John’s Castle are among the most accessible historic attractions along the Shannon navigation.
What is the best castle on Lough Erne?
Enniskillen Castle is usually considered the highlight thanks to its impressive riverside location and fascinating museums. Castle Archdale and Crom Estate are also popular stops during a Lough Erne cruise.
How many castles can you visit during a one-week boating holiday?
Depending on your route, it’s possible to visit four to seven major castles and historic sites during a week-long cruise, while still allowing plenty of time to enjoy Ireland’s villages, pubs and natural scenery.