Ishimuro-sanso (石室山荘)

090-8873-9761

☎️

090-8873-9761 ☎️

Ishimuro-sanso is a classic high-altitude mountain hut on Mt. Ontake (御嶽山), positioned around the 9th station (Kurosawa-guchi). It’s a strategic staging stop for hikers moving between the ropeway side and the upper crater/summit area—especially useful for splitting the climb, managing fatigue, and timing weather windows on an active volcano where access restrictions can change.

• Hut Overview

  • Location: Mt. Ontake, Kurosawa-guchi 9th Station (Nagano Prefecture)

  • Altitude: 2,820 m (official hut site)

  • Type: Mountain hut (staffed in season)

  • Capacity: 60 people (official hut site)

  • Operating period: July to early October (official hut site)

  • Tenting: None (some directories list no tent site)

• Access & Approaches

  Ishimuro-sanso is typically reached on the Kurosawa route—often in itineraries that start near the ropeway side and then continue upward.

  • It is explicitly described as a hut on the Kurosawa-guchi 9th station line.

  • Volcanic context: Mt. Ontake is an active volcano, and route access can be restricted depending on volcanic activity/alerts—always check current guidance before committing to upper mountain stages.

• Facilities & Comfort

  A practical, summit-oriented hut—designed for staging, not luxury.

  • Standard hut lodging/meal model (details handled via hut reservation guidance).

  • Expect typical high-mountain logistics: fixed schedules, controlled resources, and early starts.

• Food & Atmosphere

  The vibe is “mission-focused”: hikers arrive to reset, eat, sleep early, and go higher (or descend) with better timing. Clear nights can be exceptional for stargazing at this altitude.

• Routes & Alpine Context

  Ishimuro-sanso is relevant for:

  • Staging toward upper Ontake objectives from the Kurosawa side

  • Splitting long days to reduce fatigue and improve safety margins

  • Planning around weather and any volcanic-access constraints.

• When to Go

  • Best window: July–September (most stable “green season” conditions, aligned with the hut’s operating period).

  • At ~2,820 m, nights are cold even in summer; fog and wind can move in fast.

• Who Is This Hut For

  • Hikers doing a staged Mt. Ontake itinerary

  • People who want a controlled overnight before higher sections

  • Anyone who prefers hut logistics over pushing the entire route in one day.

Why This Hut Is Worth Visiting

At 2,820 m with 60 beds, Ishimuro-sanso is “infrastructure where it matters”: a well-placed high hut that makes Mt. Ontake itineraries more controllable—especially when timing, weather windows, and volcanic conditions can all dictate your safe decision-making.