シーソラプチ川Hokkaido’s Shisorapuchi River — A Day of Packrafting, From TRAILS’ Packraft Addict #78 TRAILS' Packraft Addict series covers a day of packrafting down Hokkaido's Shisorapuchi River, from Minamifurano to Lake Kanayama. 2026.09.13シーソラプチ川トリップレポート北海道パックラフト情報