Iao Needle. This area was the place of one of the most awful battles of ancient Hawaii between Kamehameha and the king of Maui. Kamehameha had brought to Maui his secret weapon, a cannon they dubbed "Robert", in order to conquer Maui. As the children and women fled to the Iao Valley, they witnessed the awful carnage of their sons and husbands being blown apart by "Robert the Cannon". The stream was so thick with bodies that the flow of the river down the mountain actually stopped. Pretty gross. So, there's kind of a mixed feeling about Kamehameha on Maui even now.