Mt. Iwadonosan

Mt. Iwadonosan (岩殿山) is a 634m rocky peak in Otsuki City, Yamanashi Prefecture. Known for being the same height as Tokyo Skytree, it is also a historically significant mountain that houses the ruins of Iwadono Castle (岩殿城跡), a Sengoku-period mountain fortress. The summit offers impressive views of Mt. Fuji and the Katsuragawa valley, and the route includes chain-assisted rock sections, making it a satisfying “rock hiking” experience despite its low elevation.

Due to typhoon damage in 2019, the traditional route from Maruyama Park / Fureai-no-Yakata (the route closest to Otsuki Station) to the summit remains closed long-term. Currently, the Hatakura Trailhead (畑倉登山口) and Asari Trailhead (浅利登山口) are the standard approaches. Some sections around the chain area (Kabuto-iwa second chain) are also restricted, with detour paths in use. Always check the latest trail conditions on-site and on the official city website.

*Timetable last verified: updated short codes can only be used on posts and fixed pages.

Map

Access

[Getting There] Otsuki Sta. → Mt. Iwadonosan
[Return] Mt. Iwadonosan → Otsuki Sta.

1. [Getting There] Otsuki Sta. → Mt. Iwadonosan

From JR Otsuki Station (大月駅), follow the signs toward Iwadono Park (岩殿公園). No bus is needed — the trailhead is within walking distance of the station.