Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The fifteen volcanoes that make up the eight principal islands of Hawaii are the youngest in a chain of more than 129 volcanoes that stretch 5,800 kilometres across the North Pacific Ocean, called the Hawaiian-Emperor seamount chain. Hawaii''s volcanoes rise an average of 4,572 metres to reach sea level from their base. The largest and most famous, Mauna Loa, has built itself up to a height of 4,169 metres. As shield volcanoes, they are built by accumulated lava flows, growing no more than 3 metres at a time to form a broad and gently sloping shape. Hawaiian volcanoes all follow a specific pattern of eruption, building, and erosion. Hawaiian islands undergo a systematic pattern of submarine and subaerial growth that is followed by erosion. An island''s stage of development reflects its distance from the Hawaii hotspot.