Not sure what the offical name of this lava tube is. I have seen it called Pele's well. This particular lava tube goes down 10 feet or so. Then it take a right angle out to the sea. Safe to say that if you fall in you won't be getting back out so easy. The constant surging water will more than likely toss you around against the rocky wall. In other words be very careful around this hole.
Another view of the lava tube as the water is sucked back out into the ocean.
One of the many lava field sinkholes located along the big island highway. Just for reference the sinkhole in this picture is about 3 buses long by 2 buses wide.