What is "bullet climbing"? Why is it not recommended by authorities?

Hello! I saw this question and guess you might be planning to climb Mount Fuji or are really interested in the topic. As an enthusiast with several climbs under my belt, I'm all too familiar with the term "bullet climbing" (dangan tozan)—every time I head up, I see the authorities' posters desperately trying to dissuade people with this approach.

So, let me break it down for you in plain terms.

What is "bullet climbing"—and why do the authorities advise against it?

First, what exactly is "bullet climbing"?

"Bullet climbing" (弾丸登山—dangan tozan) paints a vivid picture. Think of a bullet: launched in a flash—fast, fierce, and zero pauses until it hits the target.

Simply put, bullet climbing means:

Skipping mountain hut reservations, climbing within one day (often overnight), watching the sunrise, and descending immediately afterward.

A typical bullet climb looks like this:

Friday night: Drive or take a bus from Tokyo or nearby cities after work, arriving at Mount Fuji's 5th Station (trailhead) late at night.
Late night to dawn: Start climbing right away—no proper rest or altitude acclimatization—hiking all night in darkness.
Sunrise: Reach the summit (3,776m) around 4–5 AM to see the Goraikō ("Holy Sunrise").
Morning: After sunrise, descend immediately without resting.
Afternoon: Return to the 5th Station, then drive/ride home—exhausted "like a dog."

Sound like a commando-style mission? Cool and "efficient," right? Actually, this is what authorities and experienced mountaineers strongly warn against—a reckless move.

Why do authorities and seasoned climbers strongly advise against bullet climbing?

Treating Mount Fuji like a tourist checkpoint to be "speed-run" is a huge gamble with your life. Here’s why:

1. Skyrocketing risk of altitude sickness!

This is critical.

Your body needs time to adapt: At 3,776m, oxygen levels are only ≈2/3 of sea level. Your body requires gradual "altitude acclimatization."
The fatal flaw of bullet climbing: Rapid ascent overnight forces your body from near-sea level to ≈4,000m in hours—no time to adapt.
Consequences:
- Mild: Headache, nausea, vomiting, crushing fatigue—forcing you to quit.
- Severe: Potentially fatal high-altitude pulmonary/cerebral edema. Most rescue cases on Fuji involve altitude sickness—many linked to bullet climbs.

Safe approach: Stay overnight in a 7th/8th Station hut (2,700–3,000m) to acclimatize. Summit the next morning—cutting risk drastically.

2. Extreme fatigue → Bad judgment + accidents

Physical exhaustion: Hiking all night without sleep pushes you to your limit—both mentally and physically.
"Brain fogging" fatigue is real: Diminished focus, judgment, and reaction time on dark, steep, rocky trails. One misstep = slips, falls, or worse. Risk peaks during descent when exhaustion meets lowered guard.

3. Inherent dangers of night hiking

Hypothermia: Even in summer, summit temps at dawn hover near 0–5°C (32–41°F). Wind chill makes it feel colder. Stopping to rest from fatigue? Your body cools fast.
Poor visibility: Headlights only illuminate a tiny patch. Hard to spot loose rocks, trail conditions, or forks—increasing injury/lost-trekker risks.

4. A miserable experience

Even if you somehow avoid injury...

Miss all scenery while trudging in darkness.
Battling altitude sickness + fatigue—head pounding, stomach churning.
Shivering through sunrise winds—no mood for awe.
Dragging "lead-heavy" legs down the mountain—pure agony.

This isn’t fun—it’s "paying for pain."

In short:

See Mount Fuji as a friend to know slowly—not a checkbox to conquer.

Bullet climbing = High risk + Zero reward
Overnight climb = Low risk + Unforgettable experience

So, if climbing Fuji, always book a mountain hut for a relaxed two-day, one-night climb. It’s not just about safety—you’ll genuinely earn that moment on Japan’s rooftop, soaking in the sunrise’s majesty.

Remember: Getting home safely is the real summit.