To be honest, there's not a lot to see here but the trip may be worth it by also taking in the Auld Wives' Lifts - a natural rock formation which looks like a dolmen. Look out for the many carved heads on the "capstone". The Lifts are to the left of the track up to the cairn.
Best parking is near Blairskaith Quarry. Ask permission at North Blochairn.