Black Mountain [Clermont Cairn]

Standing as a prominent sentinel on the Louth-Armagh border, this Cooley Mountain summit offers a stark contrast between ancient history and modern infrastructure. The broad, peat-draped plateau is dominated by a massive telecommunications mast and a significant prehistoric passage tomb, providing expansive views across Carlingford Lough towards the granite peaks of the Mournes.

• •The Irish name Carnán Mhaighréid Náir translates as 'the cairn of noble Margaret', though the English name Clermont refers to the Earl of Clermont, an 18th-century landowner from the nearby Ravensdale estate.
• •Despite the modern intrusion of the 120-metre-tall television transmitter, the summit is a site of deep antiquity, featuring a Neolithic passage tomb that remains a significant archaeological landmark in County Louth.
• •The summit's position on the border makes it an exceptional vantage point for viewing the 'two kingdoms'; to the northeast, the Mourne Mountains of County Down are visible, including the distinctive profiles of Slieve Donard and Slieve Binnian.
• •Because of the service road required for the Clermont Carn transmission site, the peak is one of the most accessible Marilyns in the region, offering a straightforward route for walkers regardless of the weather underfoot.
• •The summit mast is a vital piece of national infrastructure, but its blinking lights and skeletal frame mean you are more likely to find a strong 4G signal here than the solitude typically associated with a passage tomb.