4.0 km (1.25 hrs )
This is one of the lesser known, and therefore quieter walks in the Blue Mountains. The walk leads to the edge of the Grose Valley with some magnificent views of the Blackheath skyline and the Grose Valley. The walk is short, so I combined this with another short walk to the nearby Flat Top and would have done some additional walks at the end of Mount Hay Road if the weather had not turned.
The walk begins at the unsignposted Fortress Ridge Trail, about 8.2 km from the great Western Highway on the Mount Hay Road. There are signs recommending the use of 4WD vehicles for the Mount Hay Road, and the road does become rough after about 10 km (just past the walk to Lockley Pylon). The sandy trail is easy to follow and only 1.5 km in length. There is the option to continue along Fortress Ridge (6 km return) or to descend to visit Darks Cave (maybe next time for me).
About 1 km further on the Mount Hay Road was the walk to Flat Top. This is a short but stiff climb to the flat plateau. The track was very overgrown, but not too difficult to follow - just lots of weaving in and around the small bushes and trees that have overgrown the track. You could see Mount Hay from the top, but nothing too exciting.