Kelud (Klut, Cloot, Kloet, Kloete, Keloed or Kelut) is a volcano located in East Java on Java in Indonesia. Like many Indonesian volcanoes and others on the Pacific Ring of Fire, Kelud is known for large explosive eruptions throughout its history. More than 30 eruptions have occurred since 1000 AD.
On May 19, 1919, an eruption at Kelud killed an estimated 5,000 people, mostly through hot mudflows (also known as "lahars"). More recent eruptions in 1951, 1966, and 1990 have altogether killed another 250 people. Following the 1966 eruption, the Ampera Tunnels were built (top and bottom) on the southwestern side of the crater to reduce (not drain out to empty) the water of crater lake and thus reduce the lahar hazard.
A strong and explosive eruption on early February 1990 produced a 7 kilometres (4 mi) high column of tephra, heavy tephra falls and several pyroclastic flows. More than thirty people were killed. Workers continued to quarry the Ampera Tunnel despite the still-hot (90-400 °C or 194-752 °F) pyroclastic flow deposits which reached as high as 25 m (82 ft) and buried the tunnel's mouth.
On October 16, 2007, Indonesian authorities ordered the evacuation of 30,000 residents living near Kelud, after scientists placed the volcano on the highest alert level, meaning that they expected an imminent eruption.