Bay of Plenty region was formed in 1989 after a nationwide review and shakeup of top-level local government in New Zealand. The new region incorporated the former counties of Tauranga, Rotorua, Whakatane and Opotiki. On 5 October 2011, the MV Rena ran aground on the Astrolabe Reef in the bay causing a large oil spill, described as New Zealand's worst ever environmental disaster. The region is subdivided into territorial authorities, which include the Western Bay of Plenty District, Tauranga City, Whakatane District, Kawerau District and Opotiki District, as well as parts of Rotorua District and the town of Rangitaiki in Taupo District. The
Bay of Plenty foreign (planted) forest areas are found in the inland parts of the region. The Kaingaroa Forest is the world's largest planted forest, comprising radiata pine mainly used for timber. The bay contains numerous islands, notably the active volcano Whakaari / White Island, which lies 50 kilometres from the coast in the eastern bay. Other large islands include (from west to east) Matakana Island, Mayor Island / Tuhua, Motiti Island, and Moutohora Island. The Waimangu Geyser – to be seen 1900–1904 – erupted frequently, was the most powerful geyser of the world and killed 4 people in 1903. In the 2006