For the most adventurous people, you can reach FOSS and also back home, through the mountains from/to different train stations:

Gotemba line:

Suruga-Oyama
Yaga
Yamakita

Fujikyu line:

Fujisan
Gekkouji
Shimoyoshida
Yoshiikeonsenmae
Kotobuki
Mitsutoge
Higashikatsura
Yamuramachi

Keio line:
Takaosan guchi

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