Mt. Kurofuyama (黒斑山)

Mt. Kurofuyama (黒斑山 Kurofu-yama) is the highest peak on the outer rim of Mt. Asama, straddling the border of Gunma and Nagano Prefectures at 2,404 meters. It is one of the most accessible viewpoints for observing the volcanic crater of Mt. Asama. The trailhead at Kurumazaka Pass offers well-maintained trails suitable for beginners in summer and popular for snow hiking with crampons or snowshoes in winter.

There are two trailheads: “Asama Tozanguchi” (near Asama Sanso lodge) and “Takamine Kogen Hotel-mae” (near Takamine Onsen).

*Timetable last checked: [sc name=”updated_date”][/sc]

Mt. Asama Volcanic Alert Level 2 (Crater Vicinity Regulation)
Mt. Asama is currently at Volcanic Alert Level 2, and entry is prohibited within approximately 2 km of the crater. The trail from Sai-no-kawara Junction to Mae-kakeyama is closed due to regulations. Mt. Kurofuyama (Omote Course and Naka Course from Kurumazaka-toge) is outside the restricted area and open for climbing.

Map

1. Going: Sakudaira Sta. / Komoro Sta. → Kurumazaka-toge

From Sakudaira Station or Komoro Station on the Hokuriku Shinkansen / Shinano Railway, take the JR Bus Kanto “Takamine Kogen Line” and get off at Asama Tozanguchi or Kurumazaka-toge (Takamine Kogen Hotel-mae).

Travel time: Approx. 54–59 min from Sakudaira Sta.
Fare: Sakudaira Sta. → Takamine Kogen Hotel-mae ¥1,380 / Komoro Sta. → Takamine Kogen Hotel-mae ¥1,050
2 buses per day. IC cards accepted. Year-round service.

Bus Timetable: Sakudaira Sta. → Kurumazaka-toge

Reference: JR Bus Kanto

2. Going: Shinjuku Sta. → Takamine Kogen Hotel-mae

From Shinjuku Station South Exit (Busta Shinjuku), take the JR Bus “Shinjuku – Saku / Komoro / Takamine Kogen” line and get off at “Takamine Kogen Hotel-mae.”

Travel time: Approx. 3 hours 46 min
Fare: ¥3,100 (Online booking ¥2,980) / Early bird ¥2,950 (Online ¥2,830)
1 bus per day. Reservation required. Wi-Fi available. Year-round service.

Bus Timetable: Shinjuku Sta. → Takamine Kogen Hotel-mae

Reference: JR Bus Kanto

3. Return: Kurumazaka-toge → Sakudaira Sta. / Komoro Sta.

From Kurumazaka-toge (Takamine Kogen Hotel-mae) or Asama Tozanguchi, take the JR Bus Kanto “Takamine Kogen Line” toward Sakudaira Station.

Travel time: Approx. 58–70 min from Takamine Kogen Hotel-mae to Sakudaira Sta.
Fare: Takamine Kogen Hotel-mae → Sakudaira Sta. ¥1,380 / Takamine Kogen Hotel-mae → Komoro Sta. ¥1,050
2 buses per day. Year-round service.

Bus Timetable: Kurumazaka-toge → Sakudaira Sta.

Reference: JR Bus Kanto

4. Return: Takamine Kogen Hotel-mae → Shinjuku Sta.

From Takamine Kogen Hotel-mae, take the JR Bus “Shinjuku – Saku / Komoro / Takamine Kogen” line and ride to the last stop at Busta Shinjuku.

Travel time: Approx. 3 hours 57 min
Fare: ¥3,100 (Online booking ¥2,980) / Early bird ¥2,950 (Online ¥2,830)
1 bus per day. Reservation required. Year-round service.

Bus Timetable: Takamine Kogen Hotel-mae → Shinjuku Sta.

Reference: JR Bus Kanto