The finest hills of the Northeast are the Mourne Mountains, a compact group of granite peaks. Slieve Donard (850 metres) is the highest mountain in Ulster, but there are others at least as worthy, notably Slieve Bearnagh and Slieve Binnian, with their rocky summit tors, haunt of rock-climbers, but still accessible to walkers. Shaped like a trident, the Mournes offer splendid circular walks, fairly short but with plenty of ascent and descent. You can also fill a full day by walking the stone wall, which follows the outer perimeter of summits.

Across Carlingford Lough is the Carlingford (or Cooley) Peninsula. It is small, but its highest summit Slieve Foye offers a long rough, rocky ridge, and the bonus of fine views across Carlingford Lough (actually an estuary) to the Mournes. The small town of Carlingford, the natural starting place has many fine mediaeval buildings.