The type of lava known as A'a (ah-ah) derives its name from the noises people exclaim as they walk over its coarse, unforgiving surface. As KP and I entered a cave, we heard screams of agony as some guy army crawled from a small opening beside us. The ground he crawled over was A'a. I asked him if there was anything worth seeing in there. Obviously frustrated and in pain, he replied "Yeah, if you like small holes." A later observation of a map of the cave revealed the long, narrow passageway he emerged from simply led to a dead end.