Most of Ireland’s big dolmens sit out in fields at the end of a walk. This one is behind a hotel car park. Aideen’s Grave is a Neolithic portal tomb in the grounds of Howth Castle, dating to around 2500 BC, and it is the second-largest of its kind in the country, behind only the Brownshill Dolmen in County Carlow. The approach is short and signposted, which makes it one of the easier prehistoric monuments to reach near Dublin.
The stones
The capstone is the thing. It measures roughly 5 metres long, 4 metres wide and 2 metres deep, an estimated 75 tons of quartzite. The tomb is aligned to the south-east, and over the centuries the capstone has slipped backwards to rest on the upper edges of the two portal stones, each about 2.5 metres high, hanging above the collapsed chamber. The original doorstone has fallen. Only Brownshill in Carlow is bigger.
Stand back a little and the scale lands better than it does up close. It is worth remembering how the thing was built: levered into place with wooden rollers, ropes and a great many people, with no metal tools and no wheels.
The legend of Aideen and Oscar
The name comes from a legend popularised by the poet and antiquarian Sir Samuel Ferguson in his 1864 poem ‘Aideen’s Grave’. In the tale, Aideen is daughter of Aenghus, ruler of Howth (in Irish Beann Éadair), and marries Oscar, a warrior and grandson of Fionn McCool. When Oscar is killed at the Battle of Gabhra, around 284 AD, Aideen dies of grief, and the poet-warrior Oisín buries her on Howth Head under the tomb.
Worth being honest about: this is a Victorian literary invention, not an ancient oral tradition, and scholars treat it as such. The monument predates the story by thousands of years. A more local folk version has Fionn McCool flinging the stones over from the Bog of Allen in County Kildare during a game of pitch-and-toss with a rival giant.
Visiting the dolmen
Park at the Deer Park Hotel car park and take the signposted steps up on the right-hand side of the hotel, beside the golf course; it is about 200 metres through the trees to the dolmen. In late spring and early summer the rhododendrons and azaleas are in full colour, though that same foliage can partly hide the tomb; a walk around the perimeter finds the clearer angles.
The elevated position opens out across the bay. On a clear day you can pick out Lambay Island, Ireland’s Eye, the city skyline and, further off, the Wicklow Mountains.
Practical information
| Item | Details |
|---|---|
| Location | Howth Castle grounds, Howth Head, Co. Dublin |
| Opening hours | The estate gates open at 7am for early golfers and walkers; the gardens run daily 09:00-18:00, with seasonal variation. The dolmen is free and open year-round. |
| Admission | Free to the dolmen and grounds. Guided tours of the castle itself run at select times and are booked separately. |
| Accessibility | The final approach has uneven ground and low stone steps, awkward for standard wheelchairs or pushchairs. |
| Getting there | DART to Howth station (about 30 minutes from the city centre), then walk or cycle to the estate. By car, follow the R105 to Howth and park at the Deer Park Hotel and golf course. |
| Facilities | Café, toilets and a gift shop within the castle grounds. |
| Website | https://howthcastle.ie |
Nearby
- Howth Castle Gardens – Terraced grounds with a 32-foot beech hedge planted in 1710 and over 200 species of flowering shrub.
- National Transport Museum of Ireland – In the former Mariners Church, with vintage trams, buses and a 10-ton revolving lighthouse lens.
- Corr Castle Ruins – A 16th-century tower house on the peninsula.
- Howth coastal walks – Cliff trails out of the village; the Black Linn Loop gives the sea views and passes the Bailey Lighthouse.
Allow about 45 minutes for the dolmen and a wander through the grounds. Parking fills on weekends, so arrive before 10.30am or take the DART. If you are continuing onto the cliff paths afterwards, check the tide times first, as some sections can be cut off in high tide or rough weather.