The mountains

The Dunkerron Mountains (Sléibhte Dhún Ciaráin) form the long, rugged range that runs along the spine of the Iveragh Peninsula between the Kenmare River and the Ballaghbeama / Bridia valleys. They sit directly north of Sneem — the dark wall of hills you see from anywhere in the village. The range stretches roughly from Mangerton in the east to the head of Ballinskelligs Bay in the west, cradling the great horseshoe of the Ring of Kerry. The highest summit is Mullaghanattin (773 m), the "Matterhorn of the Iveragh", with another dozen named peaks above 600 m. Almost all are pathless, boggy, and far more committing than their modest heights suggest — true mountain country. The Dunkerrons are separated from their larger sister range, the MacGillycuddy's Reeks, by the deep gash of the Bridia Valley and Ballaghbeama Gap. Together the two ranges make up the most concentrated area of high mountain in Ireland.

The Dunkerrons are carved from Old Red Sandstone laid down some 400 million years ago, when the land that became Ireland sat south of the equator under braided desert rivers. The rock was later folded into the great east-west ridges of the Munster Armorican fold belt — the reason every range in the south-west runs along the same axis. Their current shape is the work of ice. Successive glaciations gouged out deep north-facing corries — Coomcallee, Coomnacronia, Cummeenavrick — and dropped strings of small lakes (paternoster lakes) on their floors. The U-shaped Bridia Valley and the chasm of Ballaghbeama are textbook glacial features.

• Blanket bog across the broad ridges — bog cotton, sundews, sphagnum. • Wet heath with heather, gorse, deer-grass. • Corrie lakes holding small populations of Arctic char (a glacial relict). • Rocky crags for ravens, peregrines and occasional sea eagles. • Oakwood remnants in the sheltered valley bottoms near Tahilla and Blackwater.

The range takes its name from Dún Ciaráin — "Ciarán's fort" — the medieval territory of the O'Sullivan Mór, whose stronghold of Dunkerron Castle stood on the shore of the Kenmare River near present-day Kenmare. For centuries the high ground was used for summer grazing (buaile or "booleying"), with families moving cattle up to mountain huts each summer. The faint rectangular outlines on the upper slopes are the remains of these settlements. The range was crossed by drovers' paths and pilgrim routes long before any road — the Ballaghbeama Gap (Bealach Béime, "the pass of the notch") was the main link between the south coast and Glencar until the modern Ring of Kerry was cut along the shoreline in the 19th century.