Accessible via Hana Road, this is a must stop! Beautiful oceanside waves pounding onto the cliffside. Blowholes, hikes and a black sand beach. Register in advance. Not quite car camping, only a public cold shower, bathrooms, and a soda vending machine. Bring your own tent and camp out with everyone. It is a big place and just so you know, it is also a tourist destination, so prepare yourself for buses.
I enjoyed the views, hike down to the black sand beach.