One of my favorite things I did in Hawaii was the Makapu'u Point / Lighthouse Trail. Not because of the view you reach when you get at the top more because of the tide pools! I've never seen something like this and it's really beautiful. Also great for snorkeling - the water is so clear! The Trail is pretty easy but getting down to the tide pools can get a bit difficult not to mention to get up. It's not as difficult to get up as to get down but it's way more exhausting.