I climbed Japan’s highest mountain (which also happens to be an active volcano) with a 30L backpack, carrying less than 4kg. Here’s my Mount Fuji packing list.
It can be quite cold at night and at the summit, so I definitely recommend layering. A big jacket is not practical as you may want to shed layers and still have some protection from the chill of the wind – long sleeve clothing is very practical as a guard against sun.
It’s a mountain, so keep in mind that you will be climbing at altitude and packing only what you need will contribute towards a more positive mountain climbing experience. You could really do without a backpack and climb with only the clothes on your back – but a the temperature can drop dramatically at a moment’s notice and having a backpack to hold your warm clothes is a convenient option.
If you climb in a group, you can share the weight around so not one person is carrying all the water, all the food, etc. Having friends with you adds depth to the experience and who better to share the amazing view of the sunrise in the morning?
You can read about my climb up Fujisan (and how to get there) here:
The Arduous Ascent To The Apex of Mount Fuji
A technical shirt
A technical tee shirt
A pair of running shorts
A pair of liner socks
A pair of hiking socks
A pair of thermal leggings
Rainproof hiking pants
Light fleece (for layering)
Some 100¥ coins (for toilet)
1L Water bottle
35L backpack (total packed weight 4Kg)