Castlemahon Mountain is the most significant eminence in the rolling County Down countryside to the south of Strangford Lough. Despite being tree-shagged and transmitter-crowned it is a relatively shy hill.

The most obvious points of access are from the minor road to the south. Start at ( C'mahon SE (J563 470)) and walk up the concreted road heading northwards. This curves left through a courtyard surrounded by farmhouses and other agricultural buildings; permission does not seem to be a problem but it would be polite to enquire. From here a 4 wheel drive track continues on uphill; this is to provide access to the transmitter. You will pass a statue on the left; just after this go left at a junction up through an avenue of trees. The mast is on the right at the top of this rise, and the highest point is somewhere in the tough vegetation on its far side (no trig column has been found as of yet). The view is mostly curtailed by trees but is very fine in the directions in which it is open.

Looking at the map an even shorter route seems to suggest itself from (A (J559 469)), but enquiries at the cottage at the top of the track that leaves the road here suggested that the owner of the land (who lives at the first bungalow on the left on the way up, but was absent when I went knocking) would probably not allow access. Linkback: mountainviews.ie/summit/1368/comment/15612/