Mount Fugen Long Course
This most strenuous of the climbs has a number of trailheads, depending on the length and time trekkers want to devote to it. Starting in the town of Unzen Onsen will require a full day, while departing from Nitta Pass will cut that down to four or five hours, and leaving from the top of the ropeway will cut another 40 minutes to an hour. The weather can be fickle: you may end up on top of clouds or inside them, but it often clears to unveil a number of stunning views. There are some steep downhill sections on both the ascent and descent, but most of the climb is intermediate level. The trail crosses narrow ridges, goes through mossy valleys, and passes fascinating volcanic rock formations and the massive form of boulder-strewn Mt Heisei-shinzan, a product of the 1990 eruption that is still off-limits to climbers.