The main Hawaiian Islands are a group of inhabited islands situated in the northern Pacific Ocean. These islands stretch from Ni‘ihau to the big island of Hawai‘i (home to Mauna Loa, the tallest edifice in the world rising 9,500 m from seabed to summit). The main Hawaiian Islands lie at the southeastern end of the Hawaiian archipelago, with the uninhabited Northwest Hawaiian Islands extending toward Asia. Geologically, the main Hawaiian Islands and the Northwest Hawaiian Islands were formed by ‘hotspot’ volcanism that continues today on the island of Hawai‘i. The main Hawaiian Islands are all considered “high” islands, being significantly raised above sea level, and most exhibit both lush mountains and arid plains. The eight islands are: Hawai‘i, Maui, Koho‘olawe, Moloka‘i, Lana‘i, O‘ahu, Kaua‘i and Ni‘ihau.
The main Hawaiian Islands contain 1,200,000 people, the majority of which inhabit the island of O‘ahu. Tourism is one of the major industries in the state and brings an additional 6,400,000 visitors to the islands each year. The majority of these tourists come to Hawai‘i because of the beaches and other ocean-related activities. There has been extensive anthropogenic degradation of the marine environment in the main Hawaiian Islands due to pollution, coastal development, overfishing, and military activity.