Location
Actually, somewhere in the desert ... off the road from Riyadh to Makkah.
Leave Riyadh from the 'eye' hospital and zero your car trip meter.
The bridge just after the Diplomatic Quarter on the right will be at 5.2km.
Cross three bridges over waddis. Passing under the first of the next two bridges the trip meter will read 17.5km.
Descend through the cutting to the bottom of the escarpment. Take the exit just after the bridge (not before), trip reading 39.8km, signposted for Dirab. Go under the road to head east for the old road to Riyadh. Take the track to the left opposite a workshop, at 43km. Follow it for 3 km and park in front of the trail.