Want to go to a really secluded beach? You can find this seclusion right on Yanui Beach Phuket, this small beautiful Phuket beach is just south of Nai Harn beach tucked away between Promthep Cape and the wind power station, just take road 4233 and you will run right into it.
One thing I like about this beach is there is a small island not too far out, I have swam to this island a few times and it is a very beautiful swim, the last few times I have been to this beach I have been the only person. During the high season Yanui beach traffic picks up some, but for the most part not to many folks use it.
When you are driving any of the roads south of the island just be careful, the roads are very winedy.