Kaumana Cave, looking upflow towards the entrance. The entrance is in a county park in Hilo on the big island of Hawaii.
<a href="//commons.wikimedia.org/wiki/User:Dave_Bunnell" title="User:Dave Bunnell">Dave Bunnell</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>