Aitutaki, also traditionally known as Araura and Utataki, is the second most-populated island in the Cook Islands, after Rarotonga. It is an "almost atoll", with fifteen islets in a lagoon adjacent to the main island. Total land area is , and the lagoon has an area of between . A major tourist destination, Aitutaki is the second most visited island of the Cook Islands. Aitutaki had a population of 1,712 in 2016. The main village is Arutanga (Arutunga) on the west side. Aitutaki is sometimes described as an "almost atoll", for it consists of a lagoon within an encircling atoll, with a significant area of high land on one side. It has a maximum elevation of approximately with the hill known as Maunga Pu close to its northernmost point. The land area of the atoll is , of which the main island occupies . The Ootu Peninsula, protruding east from the main island in a southerly direction along the eastern rim of the reef, takes up out of the main island. For the lagoon, area figures between are found. Satellite image measurement suggests that the larger figure also includes the reef flat, which is commonly not considered part of a lagoon. The barrier reef that forms the basis of Aitutaki is roughly the shape of an equilateral triangle with sides in length. The southern edge of the triangle is almost totally below the surface of the ocean, and the eastern side is composed of a string of small islands including Mangere, Akaiami, and Tekopua. The western side of the atoll contains many of Aitutaki's important features including a boat passage through the barrier reef allowing for anchorage close to shore at Arutanga. Towards the south of the side is a small break in the barrier reef, allowing access for small boats to the lagoon which covers most of the southern part of the triangle. Further to the north is the bulk of the main island. Its fertile volcanic soil provides tropical fruits and vegetables. Two of Aitutaki's 15 islets (motus) are also volcanic. The rest are made of coral. Aitutaki Airport is located close to the triangle's northern point.