Overview
Truskmore (Irish: Trosc Mór, traditionally translated as ‘big cod’, though some place-name scholars suggest ‘big barren hill’) rises to 647 m (2,123 ft) on the border of County Sligo and County Leitrim. As the highest summit in the Dartry Mountains, it holds the distinction of being the county high point for both Sligo and Leitrim. The mountain sits atop a broad, wind-swept plateau bordered by dramatic cliffs, including the iconic flat-topped Benbulbin. Reaching the top requires a drive or walk up a steep, paved access road, but the effort is rewarded with unbroken views across the Connacht countryside, stretching to the Atlantic coast and the sea cliffs of Slieve League.
The Summit & County Cairns
The summit plateau is shared between two counties, marked by separate stone cairns. The Sligo high point sits at 647 m, positioned directly beside the television transmitter compound. It offers a practical resting spot, often shaded by the heavy guy-wires that anchor the mast. About 200 metres away lies the Leitrim cairn at 631 m. This marker sits on the edge of a steep, vertical drop, providing some of the most dramatic views on the mountain.
The ground between the two cairns is a patch of peat bog that can be soft and slippery, particularly after rain or during winter months. On clear days, the Leitrim cairn frames a sweeping panorama of the Dartry ridges, Lough Allen, and the distant silhouette of Knocknarea above Sligo Town. If you are standing with your back to the transmitter compound, the Sligo cairn will be to your left and the Leitrim marker to your right, past the boggy terrain.
The TV Mast & Broadcasting History
The most prominent feature on Truskmore is its 175 m lattice mast, which broadcasts television and radio signals across the north-west of Ireland and into western Northern Ireland. The site has been a cornerstone of Irish broadcasting since 1 February 1962, when it opened as the second of Telefís Éireann’s original five transmitters. The original 135 m mast carried VHF signals for over four decades before being replaced in 2009 to accommodate the digital switchover.
Today, the site is operated by 2RN, a subsidiary of RTÉ, and transmits the Saorview digital service alongside national FM stations like RTÉ Radio 1, Today FM, and Newstalk. In May 2026, 2RN issued tenders to upgrade the facility’s Aircraft Warning Light system, reflecting the ongoing technical maintenance required for the high-altitude lattice structure. Visitors frequently spot the maintenance crew using a wire elevator to service the antenna – a rare public glimpse into the mechanics of Ireland’s national broadcast network. Real-time updates regarding signal power, maintenance outages, and engineering schedules are posted on the official 2RN website. The mast compound is fenced, but the surrounding area is open for visitors to explore.
Getting There & Parking
Access to Truskmore is via a narrow, fully paved road that branches off the Gleniff Horseshoe driving loop near Ballaghnatrillick. The climb covers 9.0 km with an elevation gain of 599 m. While the average gradient is a manageable 6.65%, the final 4 km steepens significantly, featuring tight zig-zags that peak at a maximum gradient of 22%. The road is divided into two distinct sections: a gentler lower approach followed by a steeper upper climb. The final stretch is private property owned by RTÉ and is blocked by a barrier, meaning the public portion ends at the transmitter compound.
Parking is extremely limited. The lay-by beside the gate accommodates only one to three vehicles at a time. Arriving early in the morning is highly recommended, particularly during summer weekends when the loop attracts hikers and photographers. There is no entry fee, and the site is accessible year-round.
Walking & Cycling
The paved road makes Truskmore an accessible destination for walkers and cyclists alike. The ascent is straightforward, following a well-defined path that cuts through rough pastureland and past unused livestock grates. Sheep are common on the route, and the road surface is generally good, though it can become muddy near the summit. The walk to the cairns typically takes 45 to 60 minutes each way at a leisurely pace.
For cyclists, the steep upper section provides a serious workout, with the descent offering a technical challenge that requires careful braking. The broader Gleniff Horseshoe circuit (approximately 30 km) incorporates the Truskmore access road, linking it with Tievebaun, Benwiskin, and the scenic Gleniff valley.
Practical Tips & Safety
The summit is exposed and weather conditions can shift rapidly. Strong winds are common, and fog can reduce visibility to near zero, making navigation difficult. Always carry a map or reliable GPS device, as the boggy terrain between the cairns can obscure the path to the Leitrim marker. Sturdy, waterproof footwear is essential, especially in autumn and winter when the peat becomes saturated.
Dogs are welcome on the road and at the cairns, but they must be kept on a short lead near the cliff edges. There are no visitor facilities, toilets, or refreshments on-site, so bring sufficient water and snacks. The gate at the base of the final climb is approximately 2 metres high and is designed with a frame that allows visitors to step over it safely.
Nearby Attractions
Truskmore is best visited as part of a broader exploration of the Dartry Mountains. The driving loop passes several points of interest, including the ruins of an old Barytes Mill, which serves as a quiet picnic spot before the final climb. Just a short drive away, Lough Allen offers watersports and angling, with the adventure centre in Drumshanbo providing guided activities. The region’s network of single-track roads and mountain trails makes it a premier destination for outdoor enthusiasts exploring north-west Ireland.
Plan your visit around a clear morning for the best visibility, and allow time to explore the valley floor before tackling the steep final ascent.