If I had to name the most beautiful part of Oahu, it would hands down be the windward coast. Start on the south side of the island and drive around the coast up towards the north shore. 

At the southern end you’ve got the world famous snorkeling spot Hanauma Bay and Koko Head Hike plus the Halona Blowhole. 

But the drive gets unbelievably beautiful as you drive farther north. The road winds like a ribbon between white sand beaches with turquoise water and the jagged green mountains.