Trip Report by besthike editor Rick McCharles.
I first heard of this hike on Trailspotting.
… the Hoapili Trail will take you across … 200 year old lava beds to a secluded beach.
From the trailhead hike through patches of kiawe woodland and beaches scattered with sand and white coral, contrasting starkly with the black of the lava outcroppings. Eventually and suddenly the vegetation stops – a telling sign that you’re on the newest of the lava beds – and take a sharp left turn through a gate before proceeding on through fields of barren lava formations. …
I was intrigued.
You can see how far the lava had to flow from the volcano to the sea.
This is part of what is called the Hawaiian “King’s Highway”.
Past the beach I saw a four-wheel drive truck and people camping. One reference tells that wild camping is allowed there. Tempting.
Instead I only enjoyed a short break on the log swing at Keoneoio Beach.
All the Maui hiking guidebooks include Hoapili. But many references wrongly calculate the distance from La Perouse Bay to Kanaio Beach as 5.5 miles. It’s about 2mi (3.2km) one way.
I’ll not include Hoapili on our list of the best hikes in the world. I liked it. But many would find it too hot, too desolate. The jagged lava is tought on the feet, as well.
There’s definitely no water or other facilities. If you are hiking the Hoapili, you must be self-sufficient. Like this guy.
besthike.com 
Glad you had better weather than us – we were soaked to the skin by the time we’d completed this one. Not much opportunity for lazing around at the beach. Great article, and thanks for the props.
Heading out there today, glad I found this post, thanks!