Y2 南郷山（なんごうさん）
～箱根外輪山南側の代表的なハイキングコース～
Mt. Nangosan
ジオサイト解説
南郷山は、外輪山の南麓に位置する約15万年前の火山です。山を構成している溶岩は、本小松石と同じデイサイト（※１）です。南郷山の山頂付近及び山麓は、真鶴半島をはじめ伊豆諸島まで一望できる展望スポットです。また、近くには源頼朝にゆかりのある自鑑水 や小道地蔵寺屋敷堂跡があります。
※１ デイサイト：火山岩の一種。含まれる二酸化ケイ素の量が安山岩と流紋岩の中間（63～70 重量％）のもので、カリウム、ナトリウムの含有量は比較的少ないもの。
Mt. Nangosan was formed on the southeast slope of Hakone volcano during an eruption about 150 thousand years ago.
From the top of Mt. Nangosan, you can enjoy a panoramic view from the Manazuru Peninsula to the Izu Islands.
At the base of Mt. Nangosan, there is a pond called Jikansui (the suicide pond), where it’s said that Minamoto no Yoritomo, after losing the battle with the Heike clan at Mt. Ishibashiyama and fleeing into these mountains, saw himself reflected on the surface of the pond and decided to commit suicide, but the feudal warlord Doi Sanehira persuaded him not to.
From the top of Mt. Nangosan, you can enjoy a panoramic view from the Manazuru Peninsula to the Izu Islands.
At the base of Mt. Nangosan, there is a pond called Jikansui (the suicide pond), where it’s said that Minamoto no Yoritomo, after losing the battle with the Heike clan at Mt. Ishibashiyama and fleeing into these mountains, saw himself reflected on the surface of the pond and decided to commit suicide, but the feudal warlord Doi Sanehira persuaded him not to.