Take the D781 road northwest from Carnac to Erdeven - the Kerzerho alignments are on the right-hand side of the road just before you get to Erdeven. There is a layby to park. From the parking it is a short walk to the stones - you can still walk among them (in 2002) as they are much less busy than the alignments at Carnac. There is also a path which goes to the Table du Sacrifice which is worth a visit.