Take a Train from Odawara to Hakone Yumoto then bus to Lake Ashi seems to be best.
You can take a Romance Car Train from Shinjuku to Hakone Yumoto.
Walk from Hakone Yumoto Station
93 m (1 min)
Take this bus: 温泉場入口（バス）
From Kevin’s Guest House:
You can hike over Mount Kintoki and down to Hakone including Lake Ashi. It takes about 135 minutes up and 85 minutes down to Hakone and the lake.
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