Mount Rungwe is a volcanic mountain in Mbeya Region, in Tanzania's Southern Highlands. At an altitude of , it is southern Tanzania's second-highest peak. Rungwe's volcano is currently inactive. Geography Rungwe stands at the junction of the eastern and western arms of the East African Rift. It dominates the mountainous country at the north-west end of the trough that contains Lake Malawi. The Kipengere Range lies to the east, and the Poroto Mountains lie to the north. Kyejo volcano (or Kiejo) (2176 m) lies to the southeast. The Kyela Plain, which occupies the valley of the East African Rift, lies to the south, extending to Lake Malawi. The western slopes of the mountain are drained by the Kiwira River, which empties into Lake Malawi. Geology Mount Rungwe is the center of the Rungwe Volcanic Province, a region of volcanic mountains that includes Mount Rungwe, Mount Ngozi in the Poroto Mountains and Kiejo. Rungwe Volcanic Province lies at a triple junction of rift valleys. The Lake Malawi Rift extends to the southeast, the Lake Rukwa rift to the northwest, and the Usungu Rift to the northeast. The region has been volcanically active from the late Miocene to historical times. Both Rungwe and Ngozi have had Plinian eruptions since the end of the Ice Age. The region has geothermal activity, including hot springs and warm springs. Rungwe is topped with a 4-km-wide caldera, breached to the WSW. Rungwe had a large explosive eruption about 4000 years ago, and the most recent eruption was about 1200 years ago. Kyejo last erupted around 1800. Climate Mount Rungwe has a tropical montane climate. Most rainfall is during the November to April wet season, although mists and light rain occur during the dry season. Nighttime frosts are common from June to August. The southeastern slopes of these mountains receive up to of rainfall a year, the highest rainfall in Tanzania. Ecology The plant communities on Mount Rungwe vary with elevation. The surrounding lowlands are mostly miombo woodlands. Evergreen lower montane forests are found on the lower slopes of the forest reserve, particularly in the southeast. Common trees include Aphloia theiformis, Ficalhoa laurifolia, Maesa lanceolata, Trichocladus ellipticus, Albizia gummifera, and Bersama abyssinica. Upper montane forests are found up to 2600 meters elevation, forming a broken canopy of about 10–25 meters. Common trees include Albizia gummifera, Aphloia theiformis, Bersama abyssinica, Bridelia micrantha, Diospyros whyteana, Hagenia abyssinica, Macaranga kilimandscharica,