Overview
The Hill of Allen (Cnoc Alúine) rises about 206 metres (676 ft) from the western edge of the Bog of Allen in County Kildare. It is not high, but high enough in this flat corner of Kildare to see for miles. From the top, when it is open, the raised peatland spreads across Kildare, Offaly and Laois, broken only by the odd farmstead and, on a clear day, the far ridge of the Wicklow Mountains. The reason to come is the circular stone tower on the summit. The reason to plan ahead is that access to the hill, the tower and parking is not guaranteed, so check local notices first (see Practical Information).
History & Folklore
The name Cnoc Alúine gives the surrounding bog its own title, but the hill’s reputation stretches far beyond geography. In Irish mythology, it was considered the stronghold of the legendary hunter-warrior Fionn mac Cumhaill (Finn McCool). According to the tales, Fionn built a fortress on the summit and used the flat, open ground below as a training ground for his Fianna, the elite warrior band.
Recorded history adds another layer to the site. The Annals of the Four Masters record the Battle of Allen in 722 AD, where the forces of High King Fergal mac Máele Dúin met the Leinstermen led by King Murchad mac Brain Mut. Centuries later, Victorian romanticism reshaped the hill’s profile. Sir Gerald George Aylmer of Donadea commissioned a circular limestone folly in 1859 to replace an earlier wooden structure. Completed in 1863, the tower bears the inscribed names of the workmen who built it on the interior steps. Local tradition holds that during construction, a large coffin containing human bones was unearthed; villagers believed them to be Fionn’s remains and had them re-interred beneath the tower’s foundation.
The hill’s western flank is worked as a quarry, under a long-term agreement between Roadstone Dublin Ltd and Kildare County Council that has cut into the natural contour on that side. It’s the honest caveat here: this is a mythic hill with an active quarry biting its west face, and you’ll see and hear it.
The tower and the views
The tower is known as Aylmer’s Folly. Its interior steps carry the names of the men who built it, and the upper platform looks out over the peatlands when it is open to visitors. Whether the tower can be climbed on a given day is a matter for local notices, so do not count on it.
The view, where you can get it, is a full circle: south to the Curragh plains rolling toward Newbridge, and out across the peatland toward Laois and Offaly. For photographs, skip the middle of the day and aim for the hour after sunrise or before sunset, when low light picks out the texture of the stone and throws long shadows across the bog.
What to See & Do
- The tower and the hill: the climb crosses steep, wooded ground, and it is steeper and rougher underfoot than a stroll. Only go where signs and notices say the hill and tower are open.
- Heritage Week: the 2026 Kildare Heritage Week event at the tower listed specific opening and car park hours for the event. Outside such events, do not assume the same access.
- The legends and history: the Fianna tales, the 722 AD Battle of Allen and the tower’s Victorian origins are all worth reading up on before you go, particularly if you are here with older children or teenagers.
Practical Information
Access Check local notices for current hill, tower and parking arrangements before setting out. The 2026 Heritage Week event listed its own opening and car park hours, but routine access has not been confirmed from current authority notices. Follow signs, and keep outside the quarry boundary.
Getting there The hill is off the local roads near the village of Allen, west of Naas. Parking arrangements are not confirmed, so check notices and do not block gateways or narrow roads.
Facilities There are no reliable facilities at the hill itself, so bring what you need. The ground near the quarry side is uneven.
Safety The active quarry on the western side is a hazard. Stay outside its boundary, stick to marked routes and mind the warning signs.
Exploring the Wider Area
The Hill of Allen sits within a corridor of significant archaeological and natural heritage. Just a short drive north, Dún Ailinne preserves the remains of the ancient royal site of Leinster, with themes that echo the mythic stories found at Allen. To the south, Lullymore Heritage Park has a visitor centre and trails through raised bog habitat, and is the better choice for a planned visit to the bog. For a change of pace, the woodland walks and historic castle ruins at Donadea provide a relaxed afternoon extension to your visit.