Nai Harn Windmill Viewpoint, located on the road going to Laem Promthep Viewpoint just after Nai Harn Beach, and just before Ya Nui Beach. It is hard to miss it as the name Windmill Viewpoint comes from the several large windmills located at the top of the Hill, here you have an amazing view of Nai Harn Beach, Ya Nui Beach just below, and further to the south, if you are here during the high season when the water is calm, the view is just top notch. Since the viewpoint has not yet been too commercialized it's quite a quiet place to enjoy a good view.
The place has not much else to offer than the view itself, but it's still worth a stop if you are on the road, maybe before heading to Laem Promthep to catch the sunset. The island you spot just opposite the viewpoint is called Koh Man.
This is also a spot for model airplane enthusiasts, and hang gliders that uses this hill as a jump off to glide down to Nai Harn Beach. It's still quite a relaxing and peaceful location to enjoy a sunset, or just to do a stop from the beach life. It's open daily, as it might be a bit to dark to visit during the later evening. If you stay at one of the beaches like Patong Beach, Karon Beach or Kata Beach, do take the time to go for a Viewpoint trip, you can start with the Karon Viewpoint, then stop at the Windmill Viewpoint and end at Laem Propthep for the sunset.