Makapu’u Point Lighthouse Trail (Paved, Lighthouse, Military Remnants, Windward)
This would make a really great sunrise hike because it’s paved and therefore easy to navigate, and on the windward side where the sun rises most visibly. The park that contains the trail is called Kaiwi State Scenic Shoreline (8751-9057 Kalanianaole Highway, Honolulu, HI 96825 if coming from Waikiki just continue on the highway past Hanauma Bay and you can’t miss it on the right), it is free to enter. Pull in; there is a good parking lot, and take the paved trail heading up. There is a mid incline pretty much the whole way, but nothing too strenuous. The view of the ocean is unobstructed and beautiful, keep a keen eye out for whales in the wintertime. 
We saw only one on our visit and really had to stop and watch to see. There are also great views of Koko Head. It is 1 mile to the top where there is a small lookout platform, there were people in it so we just took a dirt path and made our own viewing station. Enjoy the wind and the colorful scene with the lovely lighthouse. 
Once you’ve had your fill feel free to look around at the summit. There is a plaque at the sight of a military plane crash. There are lots of military remnants and you can make your own path (which many are trodden) through the cacti to get to some the abandoned bunkers.
It struck me as funny how some cacti leaves were graffiti’d. 
When you’re through with exploration you can return the way you came, 1 mile back down. This is a great easy and scenic trail to take, and many others will be taking it with you. The next pull in continuing east on the highway is a scenic overlook of Makapu’u Head, and it is quite a beautiful sight. 