Yonshakudama
Short answer: Yonshakudama means '4-shaku shell'. A shaku is an old Japanese unit of about 30 cm, so the shell is about 120 cm across.
It's the showpiece of the Katakai Fireworks Festival in Ojiya, Niigata, held on September 9-10 each year as an offering to Asahara Shrine. According to the festival, the shell weighs about 420 kg, climbs to about 800 m and bursts into a sphere about 800 m wide. Katakai first launched one successfully on September 10, 1985, and Guinness recognized it as the largest aerial firework shell at 418 kg. That record has since passed to a 4-shaku shell launched at the Kounosu festival in Saitama on October 11, 2014. It weighed 464.826 kg, reached 907 m at the top of its burst and spread 748 m wide.
What should you know about Yonshakudama?
Quick facts. Each one stands alone and has a stable ID you can cite.
Katakai's yonshakudama weighs about 420 kg.
The Guinness record shell (2014, Kounosu) weighed 464.826 kg.
Video transcript: Yonshakudama: A 420 kg Firework Shell
DID YOU KNOW? The Yonshakudama firework is one of the largest aerial shells in the world, measuring about 1.2 m or 4 ft in diameter, and weighing over 400 kgs or nearly 900 lbs. This colossal shell is carefully hoisted into a reinforced mortar and blasted more than half a kilometer into the sky. When it detonates, it creates a gigantic sphere of light nearly 800 m or 2,600 ft wide. NOW YOU KNOW!
Burned-in captions, read frame by frame (see transcript.md) · 22.6s Reel ·
The write-up
A 420 kg firework shell. Katakai's 4-shaku shell blooms about 800 m wide.
- Exhibit A
The name
Shaku is an old Japanese length unit of about 30 cm. A 'yonshakudama' (4-shaku ball) is about 120 cm across, and Katakai is also known as the birthplace of the smaller 3-shaku shell.
- Exhibit B
The numbers
Katakai's festival puts its 4-shaku shell at 120 cm and about 420 kg, rising to about 800 m and blooming about 800 m wide.
- Exhibit C
An offering
The fireworks began as offerings to Asahara Shrine, sponsored by families and businesses to mark births, weddings or prayers for health. The festival is held on September 9-10 every year.
- Exhibit D
Record history
Katakai launched its first successful 4-shaku shell on September 10, 1985, and Guinness recognized the 418 kg shell as the largest aerial firework.
- Exhibit E
Record broken
On October 11, 2014, a 464.826 kg shell launched at Kounosu, Saitama, took the record, reaching 907 m to the top of its burst and blooming 748 m wide.
Questions people ask about Yonshakudama
What does 'yonshakudama' mean?
A 4-shaku (about 120 cm) shell.
Source: Write-up · Exhibit A (The name) · Travel to Tohoku (official tourism site): Katakai Festival; Katakai Festival: Introducing the 4-shaku shell (yonshakudama)
About how much does Katakai's 4-shaku shell weigh?
About 420 kg.
Source: Write-up · Exhibit B (The numbers) · Katakai Festival: Introducing the 4-shaku shell (yonshakudama); Discover Niigata: Katakai Fireworks Festival at Asahara Shrine
In which prefecture is the Katakai festival held?
Ojiya, Niigata.
Source: Write-up · Exhibit C (An offering) · Travel to Tohoku (official tourism site): Katakai Festival
In what year did Katakai first launch a 4-shaku shell successfully?
September 10, 1985.
Source: Write-up · Exhibit D (Record history) · Katakai Festival: Introducing the 4-shaku shell (yonshakudama); Guinness World Records (2016): Classics: Largest aerial firework shell
Where was the current Guinness record shell launched?
Kounosu, Saitama, in 2014.
Source: Write-up · Exhibit E (Record broken) · Guinness World Records (2016): Classics: Largest aerial firework shell
Test Your Knowledge
All quizzes →5 questions, all from this case file. Answers are revealed instantly.
What does 'yonshakudama' mean?
- 4-shaku shell
- Four-color flower
- Great thunder
- Night bloom
Show the answer
Answer: A. 4-shaku shell A 4-shaku (about 120 cm) shell. Source: Write-up · Exhibit A (The name) · Travel to Tohoku (official tourism site): Katakai Festival; Katakai Festival: Introducing the 4-shaku shell (yonshakudama)
About how much does Katakai's 4-shaku shell weigh?
- About 42 kg
- About 420 kg
- About 4,200 kg
- About 4 kg
Show the answer
Answer: B. About 420 kg About 420 kg. Source: Write-up · Exhibit B (The numbers) · Katakai Festival: Introducing the 4-shaku shell (yonshakudama); Discover Niigata: Katakai Fireworks Festival at Asahara Shrine
In which prefecture is the Katakai festival held?
- Niigata
- Saitama
- Osaka
- Hokkaido
Show the answer
Answer: A. Niigata Ojiya, Niigata. Source: Write-up · Exhibit C (An offering) · Travel to Tohoku (official tourism site): Katakai Festival
In what year did Katakai first launch a 4-shaku shell successfully?
- 1985
- 1945
- 2005
- 2014
Show the answer
Answer: A. 1985 September 10, 1985. Source: Write-up · Exhibit D (Record history) · Katakai Festival: Introducing the 4-shaku shell (yonshakudama); Guinness World Records (2016): Classics: Largest aerial firework shell
Where was the current Guinness record shell launched?
- Kounosu
- Katakai
- Tokyo
- Kyoto
Show the answer
Answer: A. Kounosu Kounosu, Saitama, in 2014. Source: Write-up · Exhibit E (Record broken) · Guinness World Records (2016): Classics: Largest aerial firework shell
Cite this case file
Easterling, Marcus. "Yonshakudama." The Detail Department (DetailEnjoyer), case file DD-680, last updated Dec 17, 2025. https://detailenjoyer.com/case/yonshakudama/
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