Castle Point is a beautiful place to visit and Castle Rock makes a nice walk with amazing views.
If you need only one reason to go, then how about spending the night there and wake up with the rising sun, having your morning coffee looking at the warm orange light on the sea, and the occasional jogger or dog owner walking on the beach. But just the view with the lighthouse, the riff, the lagoon and of course Castle Rock, so massive and impressive, is worth the trip.
On a clear night, you can see the milky way above the lighthouse.
Walking on the riff, you can see an incredible amount of sea shells as they are part of the rock you walk on.
You can make a short 2 hour walk to the top of Castle Rock, along the lagoon and with an breathtaking view of the coast line.
On the road we stopped near Martinbourough to visit a little glow worm cave, the main adventure being to get to the cave, driving through sheep, walking among cows and being sure we would get to the glow worms with dry feet in the gumboots, and eventually having ice cold water way above the knees!!
It was a little cave, but the magical view of the cave ceiling with all those blue like shining stars makes it a nice experience to do.