The name derives from the Irish 'An Chloch Mhór', literally translating to 'The Great Stone'.
Local folklore attributes the stone to a giant named Finn McCool, who supposedly threw it from the Cooley Mountains across the lough during a dispute.
The boulder's composition is granodiorite, which contrasts sharply with the local Silurian-aged greywacke shale of the mountain.
The stone remains stable despite its seemingly precarious balance due to the way it was deposited by glacial ice rather than human placement.
The surrounding Rostrevor Oakwood is one of the few remaining examples of native oak woodland in Northern Ireland.
The Cloughmore Stone is a massive 50-ton granite glacial erratic perched precariously on the slopes of Slieve Martin above the village of Rostrevor. Geologists identify the boulder as an erratic deposited by retreating ice sheets during the last Ice Age, composed of rock type different from the underlying mountain shale. Positioned at an elevation of approximately 300 meters, it offers expansive views across Carlingford Lough toward the Cooley Peninsula. The site is accessible via a steep, winding forest trail through the Rostrevor Oakwood National Nature Reserve. It marks a significant waypoint on the Mourne Way long-distance walking trail.
The elevated vantage point just above the stone provides the best framing of the boulder against the backdrop of Carlingford Lough.
Wear sturdy, waterproof hiking boots as the path can be muddy and uneven.
Bring a windproof jacket, as conditions at the elevation of the stone are significantly windier than at the base of the forest.
Start your hike early to secure parking at the designated forest trailheads, which fill up quickly on weekends.
Do not attempt to climb onto the stone itself, as it is a protected geological feature and potentially unstable.
Practice 'Leave No Trace' principles by carrying out all litter and staying on marked trails to protect the forest floor.
