Raghtin More, Mountain summit in County Donegal, Ireland.

Raghtin More (Irish: Reachtain Mhór), also called Slieve Keeroge, is a 502-metre mountain in Inishowen, County Donegal. Its summit carries a megalithic cairn, and the climb is usually made from Mamore Gap. From the top, Lough Swilly and the coast as far as Malin Head are visible.

A megalithic cairn stands on the summit of Raghtin More, the only structure the sources record on the mountain. Its builders and date are not documented, so the cairn is best described as a prehistoric monument rather than a dated event. The mountain rises in Inishowen, County Donegal, and is climbed from Mamore Gap.

The Irish name Reachtain Mhór appears alongside the English form Raghtin More, and the peak is also known as Slieve Keeroge. The summit cairn is a megalithic structure, the kind of prehistoric monument found across Inishowen. Walkers climbing from Mamore Gap pass it at the top.

The usual ascent begins at Mamore Gap, the pass on the R244 between Buncrana and Carndonagh, from which the summit is climbed. The ground is rough and exposed, so wear boots with ankle support and carry waterproofs; mist can hide the cairn and the coastal view toward Malin Head.

A megalithic cairn sits on the summit, reached on foot from Mamore Gap; the Swedish source gives a height of 505 m and a base width of 8.8 km, while the English article states 502 m. The nearest larger settlement is Buncrana, about 13.6 km to the south.