This was taken up on top of the Diamondhead overlook near Honolulu HI. I was pleasantly suprised to find that the whole "turquoise water" nonsense that I always see advertised wasn't nonsense at all. That water is freaking colorful! The only other ocean water I've seen has been muddy blue grayish.
The next most enjoyable thing about this view was the hike up. Being rambunctious Colorado boys, my brother and I climbed, clambered and raced up the whole 700 vertical feet (which is big out there) past struggling wealthy vacationers. They gave out shirts at the bottom saying "I conquered DiamondHead" and we just found the whole thing very amusing.
But it was a fun hike and a nice reward to be sure!