Castle Head lies on Narrow Neck Plateau, overlooking the Ruined Castle and Mt Solitary. There are excellent views from the top. The abseiling trip from Castle Head down to the Ruined Castle is fairly challenging, as it is quite exposed in places, both on and off rope.
Head along Cliff Dr from Scenic World in Katoomba. After passing several lookouts, turn left into Glenraphael Dr, which immediately turns into a dirt road. Follow the road out along Narrow Neck to a locked gate after about 3km. At one point there is a steep section which has been cemented. The parking area is about 300m past this.
Continue out along the fire trail for 800m. Just after a right hand bend, there should be a signposted track to Castle Head on your left.
The track climbs up and over the top of a hill, and then down towards the cliff edge. Not far after this the trail passes a lookout right on the cliff edge, and this is a great spot to stop and check out the views. All of the Katoomba cliffs are visible, as is the massive bulk of Mt Solitary on the far side of the Jamison Valley.
The track continues through low growing heath to Castle Head trig. The end of the trail is about 70m past here with more views of Mt Solitary, as well as Narrowneck and Cedar Creek. This is a good spot to harness up.
From the end of the trail, scramble down a few sets of ledges to the first set of chains, which are below an awkward and exposed climbdown. The first abseil goes off the left of the ridge, and is around 25m long. If you're using a 50m rope, make sure it's not a few metres short. The first person needs to swing to the right (facing the cliff) and grab a small tree. Abseiling left-handed is a help here.
The next abseil is from the pinnacle just next to where the first abseil finishes, and is about 15m from a maillon on a bolt, backed up off the tree. It goes directly down the slab to an obvious landing area, but it may be easier to work your way down ledges on the left on the rope to get going.
Scramble down and out on to the next platform. The next abseil is from two anchors - slings around a tree on the right side of the platform, and a bolt on the left. The abseil goes off the front left side of the platform. Have a look at the landing before you take off. It is fairly obvious where the correct route is. The abseil is about 15m but the anchors are about 5m back.
To get to the next abseil involves a couple of scrambles, and there are some exposed sections. Use safety lines if you have any concerns. Scramble off to the right, and then under the cliff to the point, and then down the point. Walk along the ridge until you reach a gap of about a metre, with a drop of a couple of metres. The brave or foolhardy can jump this, but it is probably better to abseil down 12m to the large tree, and then climb up.
Walk out to the nose, stepping across a narrow gap near the end (somewhat exposed), and then a final short scramble down to reach the anchors, set in a detached block. You have a couple of options here. One is to head straight off the front, a beautiful 40m abseil overhung about half way down.
You can also go off the left side in a couple of stages. This is the route to take if you only have one rope.
Either way, walk under the cliffs and along the ridge. After about 100m past the end of the cliffs, there is a tree on the left with slings around. This is a 25m drop, but there are quite a few loose rocks at the top making belaying at the bottom difficult.
Alternatively, continue along the ridge. There are two tricky scrambles, and a couple of less difficult ones. Belay people here if you have any concerns.
Not much further along you reach the saddle between Castle Head and the Ruined Castle. From here, turn left to go back to the Mt Solitary track, and left again to get back to the Golden Stairs, or right to head up to the Ruined Castle for lunch.