The mountain is most often climbed from the Nine Stones, a landmark point at the foot of Mount Leinster, about 8 miles east of Borris.

This road is closed to normal traffic and 2RN have now fenced off the transmitter mast from public access to prevent vandalism.

The Nine Stones and the car park lie on the saddle between Mount Leinster and the nearby Slievebawn (Sliabh Bán; 52°38′18.6″N 6°48′33.32″W / 52.638500°N 6.8092556°W / 52.638500; -6.8092556; 520 metres (1,710 ft)).

On Wednesday 7 September 1983 a Cessna 182Q Skylane light aircraft crashed 30 metres (100 ft) below the summit while on a flight from Birmingham to Kilkenny.

It is the highest transmission site in Ireland, and was one of the original five main Telefís Éireann television transmitters when it opened on low power in December 1962.

Today the site provides the Irish digital television service Saorview, and eight FM radio stations to a large area of South East Ireland.