Historical eventDecember 42021

Semeru

Semeru on the Indonesian island of Java erupts, killing at least 68 people.

5th anniversary in 2026

Everything on December 4Original source

In context

When
Saturday, December 4 20215 years ago
Category
Historical eventA dated happening — a battle, treaty, launch, discovery, disaster or decision — recorded on this calendar day.
Era
21st century · 2020s
Anniversary
5th in 2026
Recorded from
Wikipedia “On this day” feed

At a glance

Dates: From 2021.

What happened

Semeru is the highest mountain on the Indonesian island of Java and an active volcano located in the province of East Java in a subduction zone, where the Indo-Australian Plate subducts under the Eurasian Plate. Semeru is 3,676 m tall at its peak, making it the third tallest volcano mountain in Indonesia after Kerinci and Rinjani.

December 4 through the years

Other entries on the same calendar day, in order.

  1. 1996Murder of Fernando Balderas Sánchez and Yolanda Figueroa
  2. 1998Unity (ISS module)
  3. 2005December 2005 protest for democracy in Hong Kong
  4. 2006Jena Six
  5. 2012Canto degli italiani
  6. 2014Caucasus Emirate
  7. 20152015 Cairo restaurant fire
  8. 2017Thomas Fire
  9. 2021Semeru
  10. 2024UnitedHealth Group
  11. 2025Killing of Yasser Abu Shabab

Also in 2021

  • March 14TatmadawThe Burmese military and police forces killed at least 65 civilians during the Hlaingthaya massacre in Yangon, including those protesting…
  • March 14Hlaingthaya massacreBurmese security forces kill at least 65 civilians in the Hlaingthaya massacre.
  • September 12Siberian Light Aviation Flight 51Siberian Light Aviation Flight 51 crashes short of the runway at Kazachinskoye Airport, killing four.
  • September 162021 Luxian earthquakeA 6.0 Mw earthquake strikes Lu County, Sichuan, China, killing three and injuring more than 88.
  • September 16Inspiration4Inspiration4, the first private orbital crewed spaceflight, is launched from the Kennedy Space Center.
  • September 5Alpha CondéThe President of Guinea, Alpha Condé is captured by armed forces during a coup d'état.
  • August 142021 Haiti earthquakeA magnitude 7.2 earthquake struck in Haiti, killing at least 2,248 people and causing $1.5 billion in damages and economic loss.
  • November 5Astroworld Festival crowd crushThe Astroworld Festival crowd crush results in 10 deaths and 25 people being hospitalized

Everything we record for 2021 →

Sources

Cite this page

“Semeru”, What's On This Date, https://whatsonthisdate.com/app/event/semeru-2021-december-4, accessed October 27, 2026.

Cite the underlying source as well — the source links above go to the record this entry is adapted from.

Questions about this entry

When did Semeru happen?

December 4 2021 — 5 years ago, on a Saturday.

Where does this text come from?

Wikipedia “On this day” feed. Summaries are short adaptations that link back to the source, not reprints.

How do I cite this page?

Use the ready-made citation near the sources at the bottom of the page, and follow the source link to cite the underlying record as well.

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