[1] Exit the car park (SO210178) through a gap in the wall opposite the church (worth a look) and turn left, keeping left at the fork up the road to the canal. Turn left and follow the towpath.
[2] At bridge 112 (Pont y Parc), cross the canal and head across two fields to the road. Looking back you can see the flat-topped Table Mountain. Bear left along the road for a short distance then right up the drive to Ty Mawr, going left through a gate along a grassy track. The track leads steadily up, becoming stony and passing a building used as a bat roosting site. Near the top you bear right past the house at Laswern Fawr and follow the drive that leads to the road.
[3] Turn left for a short distance until you reach the entrance drive to a car park on your right. Follow this up and, as it swings round left into the car park, keep ahead along a grassy track past a barrier. At a fork before a ruined kiln (ahead L), keep right and continue along the track below the old spoil heaps (ignoring a path that descends R). There are glorious views north across the Usk Valley. When the wide grassy track disappears and you reach a bouldery area, follow a small stony path down on your right, which leads to a wider path. Turn left, soon entering the Craig y Cilau National Nature Reserve (information board). The track follows the line of the old tramway below the cliff.
[4] Look out for a yellow waymark and follow the path down, keeping right at the next fork down to the bottom, where there’s a junction of paths near a holly tree. Bear left along the Reserve boundary, then across an area of open common and up past another Reserve information board. On reaching a track, go left to the road.
[5] Cross the road and continue down the footpath, which leads through some woodland and then along the field edge by the trees. Before descending to the valley bottom, swing right and head east along the edge of fields, skirting round Cilau Farm. Turn left when you reach the road which leads back down to Llangattock.