On Tuesday, we visited a place that the locals call "The Aquarium". MSN Maps has the best aerial view of the area, but I can't easily embed their tool in this blog, so here is a Google MyMaps view of how to get there (click on the markers and line to get descriptions):
Park at the end of S. Makena Road near La Perouse Bay, basically where the road dead ends. Then walk back along the road towards the north along the left side of the road, about 1/4 a mile. On your left side you will pass a private estate with barbed wire fence right along the road. You will see a few large wooden cylindrical water towers just off the road, you are getting close to the trailhead. Right where the barbed wire stops following the road and turns into the trees is the trailhead, it isn't marked, but hop over the rocks at the road and it is a clear trail and easy to follow. Once out on the lava rocks along the trail, there are a few spots where the trail is difficult to follow, look for white spray-painted lines on the rocks for guidance.