Facts about Nuuanu: Nuuanu is a neighborhood on the island of Oahu. Thousands of Hawaiian warriors died in the Battle of Nuuanu in 1795. It sits on the western side of an extinct volcano. The eastern half of the volcano collapsed into the Pacific ocean, forming what is today's Kaneohe. Nuuanu has a 1200 feet lookout and a reservoir that stores 21 million gallons. Some royals are buried in Nuuanu.