Mt. Kotaro

Mount Kotaro (Kotaroyama, 2,725 m) stands at the northern end of the Shirane Range in Minami-Alps City, Yamanashi. One of Japan’s 100 Highest Mountains, it sits at the tip of the Kotaro ridge that runs north from Mount Kita (Kitadake). Because it lies off the main traverse route, few people visit it, so even when Mount Kita is crowded you can enjoy a quiet walk — and the summit is a superb viewpoint facing Mount Kita head-on.

*Timetable last checked: unverified

How to access the trailheads

1. [Outbound] Kofu Station → Hirogawara
2. [Return] Hirogawara → Kofu Station

1. [Outbound] Kofu Station → Hirogawara

Trailhead = Hirogawara (approx. 1,520 m; the South Alps Forest Road bus terminus).
From bus stop No. 6 at the south exit of JR Kofu Station, take the South Alps climbing bus on the “Kofu Station / Ryuo / Municipal Ashiyasu Parking – Yashajin-toge trailhead / Hirogawara line” and get off at Hirogawara.

Ride time: approx. 1 h 55 min
Fare: ¥2,400 + ¥300 (user cooperation fee)
Operating period: June 26 – November 3, 2026 (weekday and holiday/summer timetables differ)

Bus TimetableBus timetable from Kofu Station to Hirogawara

Reference: [Yamanashi Kotsu]

2. [Return] Hirogawara → Kofu Station

From Hirogawara, take the South Alps climbing bus on the “Kofu Station / Ryuo / Municipal Ashiyasu Parking – Yashajin-toge trailhead / Hirogawara line” and get off at Kofu Station.

Ride time: approx. 1 h 55 min
Fare: ¥2,400 + ¥300 (user cooperation fee)
Operating period: June 26 – November 3, 2026

Bus TimetableBus timetable from Hirogawara to Kofu Station

Reference: [Yamanashi Kotsu]

3. Climbing route, the crux and estimated trail times of Mount Kotaro

Mount Kotaro is most often climbed together with Mount Kita, starting from Hirogawara. From Hirogawara you climb to the Shirane-Oike hut, then up the steep Kusa-suberi to the Kotaro ridge junction (approx. 2,840 m). Following the ridge north — the opposite way from Mount Kita — brings you to Mount Kotaro.

● Standard route (via the Shirane-Oike route)
Hirogawara → (suspension bridge, forest) → Shirane-Oike hut → (steep Kusa-suberi climb) → Kotaro ridge junction → (Mae-Kotaroyama) → Mount Kotaro. The crux is the stretch from the junction to Mount Kotaro: a dashed-line route faint in creeping-pine scrub, and beyond Mae-Kotaroyama a narrow rocky ridge that drops away on one side. Because the summit is lower than the junction, you descend along the ridge on the way out and must allow for the climb back.

Standard trail times for the main sections (summer / snow-free guide)

• Hirogawara → Shirane-Oike hut: approx. 2 h 5 min (ascent, elevation gain approx. 680 m)
• Shirane-Oike hut → Kusa-suberi → Kotaro ridge junction: approx. 1 h 45 min
• Kotaro ridge junction → Mount Kotaro: approx. 1 h 50 min out / approx. 1 h back

The view
The summit of Mount Kotaro faces Mount Kita head-on and is a superb viewpoint looking straight at the great rock wall of the Kitadake Buttress. Mount Kaikoma, Mount Senjo and the Hoo Sanzan are also in full view, and you can have this grand panorama to yourself on a quiet ridge.

Recommended plan (1 night / 2 days, combined with Mount Kita)

• Day 1: Morning bus from Kofu Station to Hirogawara (arrive by midday) → Shirane-Oike hut (overnight)
• Day 2: Shirane-Oike hut → Kotaro ridge junction → out-and-back to Mount Kotaro → (on to Mount Kita if time and energy allow) → descend and take the bus from Hirogawara to Kofu Station

Even if Mount Kotaro is your sole objective, staying the night before at the Shirane-Oike hut and doing it as an out-and-back is the safe choice. A day trip leaves no margin even for strong hikers; assume one night on the mountain.

4. Huts and emergency contacts

Shirane-Oike hut (staffed; the base for climbing Mount Kotaro)

• Approx. 2,200 m. Capacity approx. 51; tent site for approx. 80 tents. About 2 hours on foot from Hirogawara.
• 2026 lodging and tent reservations are via the “Minami-Pus Reserve” online booking system (minamialps-yoyaku.jp). Phone reservations are not accepted.
• Inquiries: 090-3201-7683 (in season) / 090-8595-2236 (off-season, manager’s direct line)
• Reference: Minami-Alps City Shirane-Oike hut

Kitadake-kata-no-koya and Hirogawara-sanso

• Kitadake-kata-no-koya (on the ridge, approx. 2,830 m) is a lodging option if you continue to Mount Kita. Hirogawara-sanso is the hut at the trailhead (Hirogawara), handy for a night before or a rest after the descent. Both require reservation.

Emergency contacts

• Yamanashi Pref. Police, mountain rescue / Minami-Alps Police Station: 055-282-0110
• Minami-Alps City Tourism Association: 055-284-4204
• Hirogawara Information Center (summer): via the Minami-Alps City Tourism Association

Photo by Alpsdake