Plan around the lake, not across it
Distances on the cards are straight lines from Portumna. Use the journey planner to account for roads, crossings and your real starting point.
Best castles to visit
in and around Portumna.
Portumna opens onto a cluster of very different historic buildings around the north of Lough Derg. Stay with gardens and domestic history at Portumna and Birr, or choose the more compact tower and gateway visits in Nenagh and Roscrea. The lake helps orient the map, but it also means a straight line is not your road journey.
Explore the castles 4 places, with access explainedWhich one suits your day?
Begin beside the lake
Portumna Castle and Gardens
A Renaissance house and restored gardens.
Science in an estateBirr Castle Demesne
The Great Telescope, gardens and science galleries.
Choose a tower climbNenagh Castle
A cylindrical keep with 101 steps.
The guide includes County Galway, Offaly and Tipperary. Birr’s demesne is a public attraction around a private home; its regular garden ticket is not a castle-interior ticket.
Photo credit
Portumna castle.jpg by No machine-readable author provided. Bogman assumed (based on copyright claims)., CC BY 2.5. Resized and converted to WebP. Display may be cropped; the full photograph is linked. View full photograph.
Portumna Castle and Gardens
Portumna, County Galway · 700 m from Portumna centre, straight line
A change of scale from narrow towers to a house designed around light, symmetry and gardens.
The Burkes built Portumna in the early seventeenth century, when an impressive residence no longer needed to look like a medieval fortress. Its symmetrical front and corner towers bridge those two worlds. A fire in 1826 left the house a ruin before later state restoration.
What you will see
The ground-floor exhibition helps you read the surviving building. Outside, compare the formal garden with the kitchen garden, then decide whether to extend the day into the neighbouring forest park. The house and gardens are the visit; do not expect a complete suite of furnished upper rooms.
Explore Portumna Castle and GardensSeasonal admission
The 2026 season runs from 5 March to 11 November. Until 21 October, hours are 10:00 to 18:00, last admission 17:15. Later dates close at 17:00, last admission 16:15. Adult admission is €5. Parking, a café and toilets are listed.
Check the official visitor information ↗Sources and checks
- Office of Public WorksVisitor access and historical context. Checked .
- Fáilte IrelandHistorical context and visitor experience. Checked .
Photo credit
Birr Castle, Offaly.jpg by The original uploader was Tpower at English Wikipedia., CC BY-SA 3.0. Resized and converted to WebP. Display may be cropped; the full photograph is linked. View full photograph.
Birr Castle Demesne
Birr, County Offaly · 20.3 km from Portumna centre, straight line
For the unexpected pairing of a castle estate and the history of astronomy.
The Parsons family has been associated with Birr since 1620. The nineteenth-century Great Telescope made the demesne a place of scientific discovery as well as a family estate. That connection remains the most distinctive reason to visit.
What you will see
General admission covers the gardens, parkland, telescope and Historic Science Centre. The castle is still a private home. Its seasonal interior tours are a separate experience, and the September notice says the interior is closed. Do not buy a garden ticket expecting castle rooms.
Explore Birr Castle DemesneDemesne open; interior seasonal
The operator currently lists the demesne open daily from 09:00 to 17:30. Interior tours normally run from mid-May to August, with advance booking advised and a minimum age of 12. Public paid parking is opposite the entrance; there is no visitor car park inside. Check current ticket prices before booking.
Check the official visitor information ↗Sources and checks
- Birr Castle Demesne visitor informationVisitor access and historical context. Checked .
- Fáilte IrelandHistorical context and visitor experience. Checked .
Photo credit
Nenagh Castle.jpg by Gramscis cousin at English Wikipedia, CC BY-SA 3.0. Resized and converted to WebP. Display may be cropped; the full photograph is linked. View full photograph.
Nenagh Castle
Nenagh, County Tipperary · 25.3 km from Portumna centre, straight line
A compact visit with a memorable climb above the town.
The circular keep survives from the early thirteenth-century stronghold associated with Theobald FitzWalter. Most of the surrounding castle has disappeared, making the tower feel unusually isolated. Its thick walls and height are easier to appreciate once inside.
What you will see
The climb, rather than furnished rooms, is the experience. There are 101 steps to the top, with a low passage at the base where visitors need to stoop. Choose it if the group is comfortable with a stone spiral staircase; the view provides the reward.
Explore Nenagh CastleFree admission
Tipperary County Council lists Tuesday to Saturday opening, 10:00 to 13:00 and 14:00 to 16:00, with last admission at 15:45. Admission is free. Under-18s must be accompanied by an adult. The stairs mean this is not a step-free tower visit.
Check the official visitor information ↗Sources and checks
- Tipperary County CouncilVisitor access and historical context. Checked .
- Fáilte IrelandHistorical context and visitor experience. Checked .
Photo credit
Roscrea Castle.jpg by Graham Horn, CC BY-SA 2.0. Resized and converted to WebP. Display may be cropped; the full photograph is linked. View full photograph.
Roscrea Castle
Roscrea, County Tipperary · 32.1 km from Portumna centre, straight line
For the contrast between a medieval gateway and the later town built around it.
The castle retains its imposing gate tower and rounded corner towers around a courtyard. Beside it stands the much later Damer House, a reminder that these sites were repeatedly adapted for domestic life rather than abandoned after one historical period.
What you will see
Focus on the castle and the Black Mills displays, including the high cross. Do not choose the site expecting a tour of Damer House this year: OPW says the house is closed for works during 2026. The surrounding town adds context to the surviving gateway.
Explore Roscrea CastleSeasonal admission
The published 2026 visitor season extends from March into November, with castle and Black Mills access Wednesday to Sunday. Adult admission is €3. Confirm daily tour times with OPW before travelling. The house closure applies even when the rest of the heritage centre is open.
Check the official visitor information ↗Sources and checks
- Office of Public WorksVisitor access and historical context. Checked .
- Fáilte IrelandHistorical context and visitor experience. Checked .
Make room for the visit.
Match the ticket to the building
Birr’s general admission covers the demesne and science centre. Its private castle interior has a separate summer tour season. Roscrea’s Damer House is closed for works in 2026.
Watch the weekly timetable
Nenagh closes on Sundays and Mondays and has a lunchtime break. Roscrea’s current visitor service runs Wednesday to Sunday. These patterns can decide which pairing works.
A few useful answers
Can I see inside Birr Castle with general admission?
No. The regular ticket covers the demesne and Historic Science Centre. Interior tours have separate seasonal arrangements and the September notice says the house is closed.
Which visit involves the most obvious stair climb?
Nenagh’s tower has 101 stone steps and a low entrance passage. Choose another experience if that is unsuitable.
Is Damer House open at Roscrea?
OPW lists Damer House as closed for works during 2026. The castle and Black Mills have their own visitor arrangements.
Our choices focus on what you can see and how you can visit. Sources and checking dates appear on each card. Opening dates and admission can change. Distances are measured from Portumna centre in a straight line, not along roads. Photographs show the named buildings; their dates and licences are linked in the credits.
Explore PortumnaMore things to seeCastle guides across Ireland