haven't been on it in ages, but it is a great way to link Prince Willies to Crone.
When you're coming out of Prince Willie's carpark turn right (towards Cloon) and take the left turn 100m up the road.
Over the hump in the road and when you're descending you'll see a fireroad on the left.
Follow it for maybe half a km and then take the fireroad to the right. Down this but careful not to miss the singletrack turn left, maybe 300m down.
This is/was the start of the nice descent to the river. The grassy one is great is the wet!!